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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <!-- ESWDESDOCFILE %Z%%M% %I% %W% %G% %U% --> <title>ESW PART-FW: New Features in the OpenBIOS Tokenizer toke (A User's Guide)</title> <link rel="stylesheet" type="text/css" href="workbook.css"> </head> <body> <h1 style="text-align: center;" class="title"><a class="mozTocH1" name="mozTocId449746"></a>New Features in OpenBIOS Tokenizer toke </h1> <h1 style="text-align: center;"><a class="mozTocH1" name="mozTocId459488"></a>(A User's Guide) </h1> <div class="document-control"> <ul> <li>Updated Wed, 18 Oct 2006 at 12:39 PDT by David L. Paktor </li> </ul> </div> <p class="copyright">Copyright © 2005 International Business Machines<sup>®</sup>, All Rights Reserved.<br> Licensed under the <a href="http://www.opensource.org/licenses/cpl1.0.php">Common Public License (CPL) version 1.0</a><br> </p> <!-- =========================================================================== --><!-- =========================================================================== --> <h2><a class="mozTocH2" name="mozTocId700910"></a><a name="TOC"></a>Table Of Contents</h2> <ol id="mozToc"> <!--mozToc h1 1 h2 2 h3 3 h4 4 h5 5 h6 6--><a href="#mozTocId459488">New Features in OpenBIOS Tokenizer toke (A User's Guide)</a><br> <li><a href="#mozTocId601312">Overview</a></li> <li><a href="#mozTocId119716">Scope of this Document</a> <ol> <li><a href="#mozTocId206214">What this document does not cover: </a></li> </ol> </li> <li><a href="#mozTocId343012">Error Detection and other messages:</a></li> <li><a href="#mozTocId271949">Case Sensitivity</a><br> </li> <li><a href="#mozTocId280593">Categories of Features</a> <ol> <li><a href="#mozTocId460640">Directives</a></li> <li><a href="#mozTocId930032">Command-Line options</a></li> <li><a href="#mozTocId379181">Non-standard input, syntaxes and behavior</a></li> <li><a href="#mozTocId303703">“Tokenizer-Escape” Mode</a></li> </ol> </li> <li><a href="#mozTocId959733">Features, by Category:</a> <ol> <li><a href="#mozTocId499618">Command-Line options</a> <ol> <li><a href="#mozTocId510152">Switches</a></li> <li><a href="#mozTocId514350">Include-List Directories</a></li> <li><a href="#mozTocId515750">Trace the Creation and Invocation of FCode or "Tokenizer Escape"-mode Definitions</a><br> </li> <li><a href="#mozTocId580387">Command-Line Symbol Definitions</a></li> <li><a href="#mozTocId632060">Special-Feature Flags</a></li> </ol> </li> <li><a href="#mozTocId445349">“Tokenizer-Escape” Mode</a></li> <ol> <li><a href="#mozTocId445715">The <span style="font-family: courier new,courier,monospace; font-weight: bold;">emit-byte</span> command</a></li> <li><a href="#mozTocId446081">Other commands</a></li> <ol> <li><a href="#mozTocId446447">Standard Commands</a></li> <ol> <li><a href="#mozTocId446813">The <span style="font-family: courier new,courier,monospace; font-weight: bold;">next-fcode</span> command</a></li> </ol> <li><a href="#mozTocId447179">Non-Standard operations</a></li> <ol> <li><a href="#mozTocId447545">constant</a></li> <li><a href="#mozTocId447911">emit-fcode</a></li> </ol> <li><a href="#mozTocId448277">Additional FORTH-compatible operations</a><br> </li> </ol> </ol> <li><a href="#mozTocId649525">Directives</a> <ol> <li><a href="#mozTocId557512">Conditional Tokenization</a> <ol> <li><a href="#mozTocId686605">The Conditional-block Terminator</a></li> <li><a href="#mozTocId763728">The "False" segment-switcher</a></li> <li><a href="#mozTocId375310">Condition-Testers</a></li> <ol> <li><a href="#mozTocId104560">True/False flag on the top of the stack</a></li> <li><a href="#mozTocId956359">Existence or non-existence of an FCode or "Tokenizer Escape"-mode definition</a></li> <li><a href="#mozTocId880808">Definition or non-definition of a Command-Line Symbol</a></li> </ol> <li><a href="#mozTocId891224">Tracing the state of Conditional Tokenization</a><br> </li> </ol> </li> <li><a href="#mozTocId202222">Suspending the Duplicate-Name Test for one Definition ("Overloading")</a></li> <li><a href="#mozTocId202620">Suspending the Multi-Line Warning for one occasion</a><br> </li> <li><a href="#mozTocId203416">Controlling the Scope of Definitions</a><br> </li> <li><a href="#mozTocId314185">Evaluating Command-line Symbols </a></li> <li><a href="#mozTocId655967">Outputting Arbitrary Byte-Sequences to the FCode Binary</a></li> <li><a href="#mozTocId114013">Encoding blocks of binary data taken from a file</a></li> <li><a href="#mozTocId69109">Generating Special Text-Strings and Literals</a><br> </li> <ol> <li><a href="#mozTocId70133">Current date or time</a></li> <li><a href="#mozTocId71157">Name of the function currently being defined</a></li> <li><a href="#mozTocId72181">Input-File Name and Line Number</a></li> </ol> <li><a href="#mozTocId844437">Pre-pending PCI Headers to FCode images </a></li> <li><a href="#mozTocId931658">Modifying the PCI Header</a> <ol> <li><a href="#mozTocId504353">"Revision Level of the Vendor's ROM"</a></li> <ol> <li><a href="#mozTocId503878">Byte-Order</a></li> </ol> <li><a href="#mozTocId53081">"Last Image Indicator" bit</a></li> </ol> </li> <li><a href="#mozTocId410469">Changing the name of the Binary Output File</a></li> <li><a href="#mozTocId982642">Issuing messages at Tokenization time.</a></li> <li><a href="#mozTocId550942">Changing Special-Feature Flags from Source</a> <ol> <li><a href="#mozTocId551846">Displaying Special-Feature Flags from Source</a></li> </ol> </li> <li><a href="#mozTocId573280">Manipulating the FCode-Token-Number Assignment Counter</a></li> <ol> <li><a href="#mozTocId566072">Saving and Restoring</a></li> <li><a href="#mozTocId568474">Resetting</a><br> </li> </ol> <li><a href="#mozTocId575686">Resetting Symbols Defined in Either Mode</a></li> </ol> </li> <li><a href="#mozTocId957252">Non-standard input, syntaxes, and behavior </a> <ol> <li><a href="#mozTocId850914">Ambiguous Conditions</a> <ol> <li><a href="#mozTocId162252">Tokens expected on the same line</a></li> <li><a href="#mozTocId246601">The <span style="font-family: courier new,courier,monospace; font-weight: bold;">h#</span> <span style="font-family: courier new,courier,monospace; font-weight: bold;">d#</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">o#</span> directives </a></li> <li><a href="#mozTocId978546">The commands <span style="font-family: courier new,courier,monospace; font-weight: bold;">leave</span> <span style="font-family: courier new,courier,monospace; font-weight: bold;">?leave</span> or <span style="font-family: courier new,courier,monospace; font-weight: bold;">unloop</span> outside of a loop-control framework</a></li> <li><a href="#mozTocId73206">The commands <span style="font-family: courier new,courier,monospace; font-weight: bold;">[']</span> or <span style="font-family: courier new,courier,monospace; font-weight: bold;">'</span> followed by a name that is not a valid target</a></li> <li><a href="#mozTocId74410">The Forth word <span style="font-family: courier new,courier,monospace; font-weight: bold;">to</span> followed by a name that is not a valid target </a><br> </li> <li><a href="#mozTocId75614">The word <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span><br> </a></li> <ol> <li><a href="#mozTocId76818">Followed by an inapplicable defining-word</a></li> <li><a href="#mozTocId78022">Left unresolved</a></li> <li><a href="#mozTocId79226">Not Allowed in...</a></li> </ol> <li><a href="#mozTocId884280">The command <span style="font-family: courier new,courier,monospace; font-weight: bold;">fload</span> inside a colon-definition<br> </a></li> </ol> </li> <li><a href="#mozTocId901662">Non-Standard Synonyms for Standard Functions</a></li> <li><a href="#mozTocId732819">Non-Standard Functions or behaviors</a> <ol> <li><a href="#mozTocId522750">Alias</a></li> <li><a href="#mozTocId824541">String-Escape characters and other String-Gathering Features </a></li> <ol> <li><a href="#mozTocId945290">Quoted String-Escape Characters</a></li> <li><a href="#mozTocId758170">Embedded New-Lines</a></li> <li><a href="#mozTocId42456">Hex-Sequence Processing </a></li> <li><a href="#mozTocId150131">C-Style String-Escape Characters</a></li> </ol> <li><a href="#mozTocId40998">The ABORT" (Abort-Quote) command</a></li> <li><a href="#mozTocId526780">Conveniently Convert Short Character-Sequence to Number</a></li> <ol> <li><a href="#mozTocId53626">Left-Justified</a><br> </li> </ol> <li><a href="#mozTocId54171">F['] ("Eff-Bracket-Tick-Bracket")</a></li> <ol> <li><a href="#mozTocId54716">F['] in "Normal Tokenization" Mode</a></li> <li><a href="#mozTocId55261">F['] in "Tokenizer-Escape" Mode</a><br> </li> </ol> <li><a href="#mozTocId887752">Shell-Environment Variables in File-Names</a><br> </li> </ol> </li> <li><a href="#mozTocId505746">Featured behaviors, supported by this Tokenizer, that are not mentioned in the Standard</a> <ol> <li><a href="#mozTocId530910">User-Defined Macros</a><br> </li> <li><a href="#mozTocId539069">Multiple device-nodes</a></li> <ol> <li><a href="#mozTocId540605">Global Definitions</a><br> </li> </ol> <li><a href="#mozTocId354426">Multiple FCode-block Images</a></li> <li><a href="#mozTocId232809">Multiple PCI-Image</a></li> </ol> </li> </ol> </li> </ol> </li> <li><a href="#mozTocId194505">Examples:</a> <ol> <li><a href="#mozTocId544211">Example #1:</a></li> <li><a href="#mozTocId80432">Example #2: </a></li> <li><a href="#mozTocId455242">Example #3:</a></li> <li><a href="#mozTocId861304">Example #4:</a></li> <li><a href="#mozTocId866180">Example #5:</a><br> </li> </ol> </li> </ol> <h2><a class="mozTocH2" name="mozTocId601312"></a>Overview</h2> <!-- ...................................................................................... --> <p>The goal of this project is to produce an FCode Tokenizer that can both be used in-house and be presented to third-party vendors, VARs and the like, as a professional-quality tool for their use, without adversely affecting IBM's Intellectual-Property rights.</p> <p>We are using, as a starting basis, the Open-Source tokenizer that is available from the <a href="http://openbios.org/">OpenBIOS project</a> . </p> <p>We expect to be able to deliver this tool to our vendors by returning our modifications to the OpenBIOS project, from whence it can be obtained openly by anyone. </p> <h2><a class="mozTocH2" name="mozTocId119716"></a>Scope of this Document</h2> <!-- ...................................................................................... --> In order to achieve the first part of the goal -- making it suitable for in-house use -- a number of features were added that are not covered in the IEEE-1275 Standard for Boot Firmware (also referred to herein simply as "the Standard"). <p>This document describes those <a href="#Categories_of_Features">features</a> and how they are used. </p> <p>There will be a brief overview of <a href="#Error_Detection_and_other_messages:">Error Detection</a> and other messages.</p> <p>There will be some <a href="#Examples:">examples</a> at the end.<br> </p> <h3><a class="mozTocH3" name="mozTocId206214"></a>What this document does not cover:<br> </h3> <ul> <li>Standard behavior, particularly conversion between ANSI / IEEE-1275 Standard Forth and IEEE-1275 Standard FCode, and standard Tokenizer Macros. These are expected and will be regarded as "presumed" by this document.</li> <li>Changes to older versions of the OpenBIOS Tokenizer.</li> <li>A complete list of Tokenization Source Errors detected and reported.</li> <li>A complete list of conditions that generate WARNING or ADVISORY messages.</li> <li>A complete list of FATAL conditions.<br> </li> <li>Support for <a href="localvalues.html">IBM-Style Local Values</a>. That is the subject of a separate writeup.</li> </ul> <!-- =========================================================================== --> <!-- =========================================================================== --> <h2><a class="mozTocH2" name="mozTocId343012"></a><a name="Error_Detection_and_other_messages:"></a>Error Detection and other messages:</h2> The Tokenizer is capable of producing the following kinds of messages:<br> <ul> <li>FATAL</li> <li>ERROR</li> <li>WARNING</li> <li>ADVISORY</li> <li>MESSAGE generated by the User.</li> <li>TRACE-NOTE<br> </li> </ul> <p>A <span style="font-style: italic; font-weight: bold;">FATAL</span> condition is sufficient cause to immediately stop activity. It is usually (but not always) a symptom of a system failure, rather than a result of User input.</p> <p><a name="An_ERROR"></a>An <span style="font-style: italic; font-weight: bold;">ERROR</span> occurs as a result of User input. It is a condition sufficient to make the run a failure, but not to stop activity. Unless the <span style="font-family: courier new,courier,monospace; font-weight: bold; font-style: italic;">-i</span> <a href="#Ignore_Errors_option">("Ignore Errors")</a> <a href="#Command-Line_options_">Command-Line option</a> has been specified, the production of a Binary Output file will be suppressed and theTokenizer will exit with a non-zero status, if an Error Message has been issued. <br> </p> <p><a name="A_WARNING"></a>A <span style="font-weight: bold; font-style: italic;">WARNING</span> is issued for a condition that, while not necessarily an error, might be something to avoid. E.g., a deprecated feature, or a feature that might be incompatible with other Standard tokenizers.</p> <p><a name="Advisories"></a>An <span style="font-weight: bold; font-style: italic;">ADVISORY</span> message is issued for a condition that is a response to User input, and where processing continues unchanged, but it is nonetheless (in this author's opinion) worthwhile to give the User a "heads-up" to make sure that what you got is what you wanted. <span style="font-weight: bold; font-style: italic;">ADVISORY</span> messages are only displayed when the <a style="font-style: italic; font-weight: bold;" href="#verbose_option">verbose</a> <a href="#Command-Line_options_">Command-Line option</a> is selected. </p> <p> A User-generated <span style="font-weight: bold; font-style: italic;">MESSAGE</span> -- unsurprisingly -- is a message generated by the User via any of the <a href="#User_Messages">directives</a> supported for that purpose.<br> </p> <p><a name="Trace_Notes"></a>A <span style="font-weight: bold; font-style: italic;">TRACE-NOTE</span> is issued if the <a href="#Trace_Symbols">Trace-Symbols</a> feature is activated, whenever a symbol on the Trace-List is either created or invoked.<br> </p> <p><a name="Message_Format"></a>Each message of the above types is accompanied by the name of the source file and the line number in which the condition that triggered it was detected, as well as the current position to which data is being generated into the Binary Output. If a PCI Header is in effect, the position relative to the end of that PCI Header will also be shown; this is to maintain consistency with the <a href="detok.html#with_offsets">"offsets</a>" displayed by the <a href="detok.html">DeTokenizer</a><br> </p> <p><a name="Errors_Ignored"></a> The Tokenizer typically runs through to completion of the source file, displaying an ERROR message for each error it encounters (I.e., it does not "bail" after the first error). If the <span style="font-family: courier new,courier,monospace; font-weight: bold; font-style: italic;">-i</span> <a href="#Ignore_Errors_option">("Ignore Errors")</a> <a href="#Command-Line_options_">Command-Line option</a> has been specified, the Tokenizer will attempt to produce binary output for each error, as far as is feasible, and will produce a Binary Output file. While this practice is not recommended, the author acknowledges that it might be useful in some limited circumstances.</p> At the end of its run, the Tokenizer will print a tally of the number of each type of message that was generated.<br> <h2><a name="mozTocId271949"></a><a name="Case_Sensitivity"></a>Case Sensitivity</h2> Although Command-Line option <a href="#Command_Line_Switches">switches</a> are case-sensitive, this Tokenizer is insensitive to the distinctions between upper- or lower- -case characters in all other matters: in Command-Line <a href="#Symbol_Definitions">symbol-definitions</a> and <a href="#Special_Feature_Flags">Special-Feature Flag</a> settings and in the Input Source.<br> <p>Character-case is preserved in string sequences and in the assignment of names of headered definitions, but is ignored for purposes of name-matching. Case sensitivity of filenames, of course, is dependent on the Host Operating System.<br> </p> <p>This Tokenizer supports a pair of Special-Feature Flags that will enable the User to <a href="#Token_Name_Cases">over-ride the preservation of character-case</a> in the assignment of names of headered definitions. </p> <h2><a class="mozTocH2" name="mozTocId280593"></a><a name="Categories_of_Features"></a>Categories of <a href="#Features_by_Category">Features</a></h2> <!-- ...................................................................................... --> The features described in this document fall into four categories:<br> <ol> <li><a href="#Directives">Directives</a></li> <li><a href="#Command-Line_options">Command-Line options</a></li> <li><a href="#Non-standard_input_syntaxes">Non-standard</a> input, syntaxes, and behavior</li> <li>Options available within “<a href="#Tokenizer-Escape_Mode">tokenizer-escape</a>” mode (I.e., within the scope of a <span style="font-family: courier new,courier,monospace; font-weight: bold;">tokenizer[ ... ]tokenizer</span> block).</li> </ol> <h3><a class="mozTocH3" name="mozTocId460640"></a><a name="Directives"></a>Directives</h3> <a href="#Directives_">Directives</a> are commands that occur within the body of the Tokenization Source File, but are not part of the FCode program itself. They are recognized by the Tokenizer and cause it to perform special actions that might serve such diverse functions as:<br> <ul> <li>Printing a message to the Standard Output during the Tokenization process</li> <li>Controlling whether selected passages of the Source are processed or ignored (also called Conditional Compilation or Conditional Tokenization)</li> <li>Outputting arbitrary sequences of bytes to the FCode binary file</li> </ul> <h3><a class="mozTocH3" name="mozTocId930032"></a><a name="Command-Line_options"></a>Command-Line options</h3> <a href="#Command-Line_options_">Command-Line options</a> are, as the name suggests, switches that can be set on the command-line when the Tokenizer is invoked. They affect behaviors such as:<br> <ul> <li>The verbosity of output during the Tokenization process</li> <li>Definition of symbols that feed into some of the Conditional Tokenization Directives<br> </li> <li>Allowing output to be produced even when errors have been detected.</li> <li>Selectively enabling variants of Non-standard input, syntaxes, and behavior<br> </li> </ul> <h3><a class="mozTocH3" name="mozTocId379181"></a><a name="Non-standard_input_syntaxes"></a><a href="#Non-standard_input_syntaxes_">Non-standard input</a>, syntaxes and behavior</h3> Certain sequences of source code that are not covered by the IEEE-1275 Standard are, nonetheless, recognized by this Tokenizer and cause it to produce valid FCode. Examples of these include:<br> <ul> <li>"C"-style escape characters in strings</li> <li>Sun-style versus Apple-style implementation of the command <span style="font-weight: bold; font-family: courier new,courier,monospace;">ABORT"</span> <br> </li> <li>IBM-style Local-Values</li> </ul> In order to accommodate the conflicting goals of standard-compliance and convenience, non-Standard variants will be selectively enabled by a set of Command-Line options known as "<a href="#Special_Feature_Flags">Special-Feature Flags</a>" <h3><a class="mozTocH3" name="mozTocId303703"></a><a name="Tokenizer-Escape_Mode"></a>“Tokenizer-Escape” Mode</h3> Section C.3.1 of the IEEE-1275 Standard describes “<a href="#Tokenizer-Escape_Mode_">tokenizer-escape</a>” mode and its basic command, <a href="#emit_byte"><span style="font-family: courier new,courier,monospace; font-weight: bold;">emit-byte</span></a> The OpenBIOS Tokenizer toke, while it does not have a full FORTH capability, does support a few additional Forth-style commands that can be used to:<br> <ul> <li>Define and retrieve named constants</li> <li>Create aliases</li> <li>Set the value of the next FCode-token<br> </li> </ul> <!-- =========================================================================== --> <!-- =========================================================================== --> <h2><a class="mozTocH2" name="mozTocId959733"></a><a name="Features_by_Category"></a>Features, by Category:</h2> The following sections will supply a complete list of the new features, organized by category.<br> <!-- ...................................................................................... --> <h3><a class="mozTocH3" name="mozTocId499618"></a><a name="Command-Line_options_"></a>Command-Line options:</h3> Command-Line option Switches are <a href="#Case_Sensitivity">case-sensitive</a>; their arguments, where applicable, are not.<br> <br> <h4><a class="mozTocH4" name="mozTocId510152"></a><a name="Command_Line_Switches"></a>Switches</h4> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">-h</span> or <span style="font-family: courier new,courier,monospace; font-weight: bold;">-?</span></li> </ul> <div style="margin-left: 40px;">Print a brief help message and then exit. </div> <ul> <li><a name="verbose_option"></a><span style="font-weight: bold; font-family: courier new,courier,monospace;">-v</span></li> </ul> <p style="margin-left: 40px;">Verbose -- print additional messages (including <a href="#Advisories">Advisories</a>) during tokenization.<br> </p> <ul> <li style="font-weight: bold; font-family: courier new,courier,monospace;"><a name="Ignore_Errors_option"></a>-i</li> </ul> <p style="margin-left: 40px;">Ignore Errors. Generate a Binary Output <a href="#Errors_Ignored">even if errors were reported</a>. </p> <ul> <li><a name="Binary_Output_Name_option"></a><span style="font-family: courier new,courier,monospace; font-weight: bold;">-o <OutputFileName></span></li> </ul> <p style="margin-left: 40px;">Direct the Binary Output (FCode result of Tokenization) to the named file instead of to the <a href="#Binary_Output_File_Name_Default">default-named file</a>. This option is not valid when multiple input files are named. </p> <ul> <li><a name="FLoad_List_option"></a><span style="font-family: courier new,courier,monospace; font-weight: bold;">-l</span></li> </ul> <p style="margin-left: 40px;">FLoad List -- Collect the names of <span style="font-family: courier new,courier,monospace; font-weight: bold;">fload</span>ed files into an FLoad-List File. The names collected are in the same form as they were presented in the <span style="font-family: courier new,courier,monospace; font-weight: bold;">fload</span> statements. </p> <p style="margin-left: 40px;">The name of the FLoad-List File is derived from the name of the Binary Output File, by replacing its extension with <span style="font-family: courier new,courier,monospace; font-weight: bold;">.fl</span> , or, if the Binary Output File name had no extension, merely appending the extension <span style="font-family: courier new,courier,monospace; font-weight: bold;">.fl<br> </span></p> <p style="margin-left: 40px;">The Binary Output File name used for this purpose is either the one specified <a href="#Binary_Output_Name_option">on the Command Line</a>, or the one created by <a href="#Binary_Output_File_Name_Default">default</a>. <br> </p> <ul> <li><a name="Depncy_List_option"></a><span style="font-family: courier new,courier,monospace; font-weight: bold;">-P</span> (Note: Switch is upper-case)<br> </li> </ul> <p style="margin-left: 40px;">Dependency List -- Collect the fully-resolved pathnames of <span style="font-family: courier new,courier,monospace; font-weight: bold;">fload</span>ed and <a href="#ENCODE_FILE">ENCODE</a>d files into a Dependency-List File. The names collected are in the form that is presented to the Host Operating System: <a href="#Shell_Env_Vbles_in_File_Names">Shell Environment Variables</a> and related expressions will be fully expanded, and the directory within the <a href="#Include_List">Include-List</a> in which the file was found will be attached.<br> </p> <p style="margin-left: 40px;">The name of the Dependency-List File will be the same as that of the FLoad-List File, except that its extension will be <span style="font-family: courier new,courier,monospace; font-weight: bold;">.P</span> instead of <span style="font-family: courier new,courier,monospace; font-weight: bold;">.fl</span> </p> <ul> <li>If an FLoad List or a Dependency List is being collected, the names of any files that cannot be read, for any reason, will be collected into a Missing-Files-List file.</li> </ul> <p style="margin-left: 40px;">The name of the Missing-Files-List file will be the same as that of the FLoad-List File except that its extension will be <span style="font-family: courier new,courier,monospace; font-weight: bold;">.fl.missing</span> instead of <span style="font-family: courier new,courier,monospace; font-weight: bold;">.fl</span></p> <p style="margin-left: 40px;">The Missing-Files-List file will not be created if all of the files are read successfully.<br> </p> <p style="margin-left: 40px;">If the name of the Binary Output File is <a href="#Binary_Output_File_Name_Directive">changed by a directive</a> embedded within the Tokenization Source File, that will not alter the names of the FLoad-List, Dependency List or Missing-Files-List files.</p> <h4><a class="mozTocH4" name="mozTocId514350"></a><a name="Include_List"></a>Include-List Directories</h4> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">-I directory</span> (Note: Switch is upper-case)</li> </ul> <p style="margin-left: 40px;">This Tokenizer supports the notion of an Include-List. The User creates the Include-List by specifying a number of <span style="font-family: courier new,courier,monospace; font-weight: bold;">-I directory</span> pairs on the Command-Line. All file-reads, whether for an <span style="font-family: courier new,courier,monospace; font-weight: bold;">fload</span> command or an <a href="#ENCODE_FILE"><span style="font-family: courier new,courier,monospace; font-weight: bold;">encode-file</span></a> directive, will involve a search for the named file through the directories of the Include-List, in the order they were supplied on the Command-Line. </p> <p style="margin-left: 40px;">If no Include-List is created, file-reads are relative to the Current Working Directory. If an Include-List <span style="font-style: italic;">is</span> created, file-reads are restricted to the directories within it. For the Current Working Directory to be included in the file-search, it must be specified explicitly. <span style="font-family: courier new,courier,monospace; font-weight: bold;">-I<big>.</big></span> will accomplish that quite effectively.<br> </p> <h4><a name="mozTocId515750"></a><a name="Trace_Symbols"></a>Trace the Creation and Invocation of FCode or "Tokenizer Escape"-mode Definitions</h4> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">-T <</span><span style="font-family: courier new,courier,monospace;">symbol</span><span style="font-family: courier new,courier,monospace; font-weight: bold;">></span> (Note: Switch is upper-case)</li> </ul> <p style="margin-left: 40px;">This Tokenizer supports the notion of a "Trace-List". The User creates the Trace-List by specifying a number of <span style="font-family: courier new,courier,monospace; font-weight: bold;">-T <symbol></span> pairs on the Command-Line.<br> </p> <p style="margin-left: 40px;">When a name is defined, whether as an FCode, an alias, a Macro or anything else, either in normal tokenization mode or "Tokenizer Escape"-mode, if it matches a symbol that has been added to the Trace List, a <a href="#Trace_Notes">Trace Note</a> Message will be issued indicating that a definition of that name has been created. Subsequent <a href="#Trace_Notes">Trace Note</a> Messages will be issued when the definition of that name is invoked.</p> <p style="margin-left: 40px;">This "<span style="font-weight: bold; color: rgb(0, 80, 178);">Trace-Symbols</span>" feature can be helpful during maintenance of Legacy code, for instance, when multiple symbols carry the same name.<br> </p> <h4><a class="mozTocH4" name="mozTocId580387"></a><a name="Symbol_Definitions"></a>Command-Line Symbol Definitions</h4> <ul> <li style="font-family: courier new,courier,monospace;"><a name="Define_Command-Line_symbol"></a><span style="font-weight: bold;">-d Symbol</span>[<span style="font-weight: bold;">=Value</span>]</li> </ul> <p style="margin-left: 40px;">Define a Command-Line Symbol. Optionally, assign a value to it. If you wish the "value" to contain spaces or quotes, you can accomplish that using the shell escape conventions. This sequence may be repeated. Once a Symbol is defined on the command-line, it stays in effect for the duration of the entire batch of tokenizations (i.e., if there are multiple input files named on the command line). Command-Line Symbols can be <a href="#Definition_or_non-definition_of_a">tested</a> for purposes of Conditional Tokenization, or their assigned values can be <a href="#Evaluating_Command-line_Symbols">Evaluated</a>.<br> </p> <h4><a class="mozTocH4" name="mozTocId632060"></a><a name="Special_Feature_Flags"></a>Special-Feature Flags<br> </h4> <ul> <li style="font-family: courier new,courier,monospace;"><span style="font-weight: bold;">-f</span> [<span style="font-weight: bold;">no</span>]<<span style="font-weight: bold;">FlagName</span>> </li> </ul> <p style="margin-left: 40px;">The Tokenizer recognizes a specific set of Special-Feature Flag-names; each is associated with a specific non-Standard variant behavior. Pass the Flag-name as an argument to the <span style="font-family: courier new,courier,monospace; font-weight: bold;">-f</span> switch to enable the behavior; to disable it, precede the Flag-name with the optional string <span style="font-family: courier new,courier,monospace; font-weight: bold;">No</span> <br> </p> <p style="margin-left: 40px;">The settings of the Special-Feature Flags can also be <a href="#Changing_C-L_Flags_from_Source">changed</a> or <a href="#Displaying_C-L_Flags_from_Source">displayed</a> from within the Source Input File<br> </p> <p style="margin-left: 40px;">The Special-Feature Flags are all initially set to be enabled, except where noted.<br> </p> <p style="margin-left: 40px;">The Flag-names and their associated Special-Features are as follows:</p> <ul> <ul> <li><a name="SF_Flag_Loc_Val"></a><span style="font-family: courier new,courier,monospace; font-weight: bold;">Local-Values</span></li> </ul> </ul> <p style="margin-left: 120px;">Support IBM-style <a href="localvalues.html">Local Values</a> ("LV"s). Initially disabled. </p> <ul> <ul> <li><a name="SF_Flag_LV_Leg_Sep"></a><span style="font-family: courier new,courier,monospace; font-weight: bold;">LV-Legacy-Separator</span></li> </ul> </ul> <p style="margin-left: 120px;">Allow Semicolon for Local Values <a href="localvalues.html#Separation_Character_between_Initialized">Separator</a> ("<a href="localvalues.html#Disallow_Legacy">Legacy</a>"). </p> <ul> <ul> <li><a name="SF_Flag_LV_Leg_Mssg"></a><span style="font-family: courier new,courier,monospace; font-weight: bold;">LV-Legacy-Message</span></li> </ul> </ul> <p style="margin-left: 120px;">Display a <a href="localvalues.html#Legacy_Separator">Warning Message</a> when Semicolon is used as the Local Values Separator. </p> <ul> <ul> <li><a name="SF_Flag_AB_Q"></a><span style="font-family: courier new,courier,monospace; font-weight: bold;">ABORT-Quote</span></li> </ul> </ul> <p style="margin-left: 120px;">Allow <a href="#SFeat_AB_Q">ABORT"</a> macro. </p> <ul> <ul> <li><a name="SF_Flag_Sun_AB_Q"></a><span style="font-family: courier new,courier,monospace; font-weight: bold;">Sun-ABORT-Quote</span></li> </ul> </ul> <p style="margin-left: 120px;">ABORT" with <a href="#SFeat_Sun_AB_Q">implicit IF ... THEN</a> </p> <ul style="font-family: courier new,courier,monospace;"> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;"><a name="SF_Flag_AB_Q_Throw"></a>Abort-Quote-Throw</span></li> </ul> </ul> <p style="margin-left: 120px;">Use <span style="font-family: courier new,courier,monospace; font-weight: bold;">-2 THROW</span> , rather than <a href="#Abort_Quote_Abort"><span style="font-family: courier new,courier,monospace; font-weight: bold;">ABORT</span></a>, in an <a href="#SFeat_AB_Q">Abort"</a> phrase</p> <ul style="font-family: courier new,courier,monospace;"> <ul> <li><a name="SF_Flag_Str_Rem_Esc"></a><span style="font-family: courier new,courier,monospace; font-weight: bold;">String-remark-escape</span></li> </ul> </ul> <p style="margin-left: 120px;">Allow <a href="#SFeat_Str_Rem_Esc">"\ (Quote-Backslash)</a> to interrupt string parsing. </p> <ul> <ul> <li><a name="SF_Flag_Hex_Rem_Esc"></a><span style="font-family: courier new,courier,monospace; font-weight: bold;">Hex-remark-escape</span></li> </ul> </ul> <p style="margin-left: 120px;">Allow <a href="#SFeat_Hex_Rem_Esc">\ (Backslash)</a> to interrupt <a href="#Hex_Seq_Procg">hex-sequence parsing</a> within a string. </p> <ul> <ul> <li><a name="SF_Flag_C_Str_Esc"></a><span style="font-family: courier new,courier,monospace; font-weight: bold;">C-Style-string-escape</span></li> </ul> </ul> <p style="margin-left: 120px;">Allow the <a href="#C-Style_String-Escape_Characters"><big><b>C</b></big>-style String-Escape</a> pairs <span style="font-family: courier new,courier,monospace; font-weight: bold;">\n</span> <span style="font-family: courier new,courier,monospace; font-weight: bold;">\t</span> and <a href="#SFeat_BS_xx"><span style="font-family: courier new,courier,monospace; font-weight: bold;">\xx\</span></a> to be treated as special characters in string parsing. </p> <ul> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">Always-Headers</span></li> </ul> </ul> <p style="margin-left: 120px;">Over-ride occurrences of the Standard directive <span style="font-family: courier new,courier,monospace; font-weight: bold;">headerless</span> in the Source with -- effectively -- <span style="font-family: courier new,courier,monospace; font-weight: bold;">headers</span> to make all definitions have a header. Occurrences of the directive <span style="font-family: courier new,courier,monospace; font-weight: bold;">external</span> will continue to behave in the Standard manner. Initially disabled. </p> <ul> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">Always-External</span></li> </ul> </ul> <p style="margin-left: 120px;">All definitions will be made as though under the <span style="font-family: courier new,courier,monospace; font-weight: bold;">external</span> directive; occurrences of either Standard directive <span style="font-family: courier new,courier,monospace; font-weight: bold;">headerless</span> or <span style="font-family: courier new,courier,monospace; font-weight: bold;">headers</span> in the Source will be over-ridden. This Special-Feature Flag will also over-ride the <span style="font-family: courier new,courier,monospace; font-weight: bold;">Always-Headers</span> Special-Feature Flag in the event that both have been specified. Initially disabled. </p> <ul> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;"><a name="Warn_if_Duplicate_Flag"></a>Warn-if-Duplicate</span></li> </ul> </ul> <div style="margin-left: 120px;">Display a <a href="#A_WARNING">WARNING</a> message whenever a definition is made whose name duplicates that of an existing definition. Disabling this flag will suspend the duplicate-names test globally, until it is re-enabled. A Directive is supported that will <a href="#The_OVERLOAD_Directive">suspend the test for the duration of only a single definition</a>, without affecting global behavior. </div> <ul> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;"><a name="Obso_FCode_Warning"></a>Obsolete-FCode-Warning</span></li> </ul> </ul> <div style="margin-left: 120px;">Display a <a href="#A_WARNING">WARNING</a> message whenever an FCode function is invoked that the Standard identifies as "obsolete". </div> <ul> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;"><a name="Trace_Condls"></a>Trace-Conditionals</span></li> </ul> </ul> <div style="margin-left: 120px;">Issue <a href="#Advisories">Advisory Messages</a> about the <a href="#Tracing_Conditional_State">state of</a> <a href="#Conditional_Tokenization">Conditional Tokenization</a>. (Remember that <a href="#Advisories">Advisory Messages</a> are displayed only if the "verbose" option <a href="#verbose_option"><span style="font-weight: bold; font-family: courier new,courier,monospace;">-v</span></a> is set.) Initially disabled. </div> <ul> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;"><a name="Token_Name_Case_Upper"></a><a name="Token_Name_Cases"></a>Upper-Case-Token-Names </span> </li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;"><a name="Token_Name_Case_Lower"></a>Lower-Case-Token-Names </span> </li> </ul> </ul> <div style="margin-left: 120px;">When outputting the names of headered functions ("Token-Names") to the Binary Output File, over-ride the character-case in which the names appeared in the Source, and convert them to Upper- or Lower- -Case, respectively. (These flags do not affect text string sequences, whose character-case is always preserved.) Initially disabled.<br> </div> <ul> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;"><a name="Big_End_PCI_Rev_Level"></a>Big-End-PCI-Rev-Level</span></li> </ul> </ul> <div style="margin-left: 120px;">Save the "<a href="#PCI_Rev_Level">Revision Level of the Vendor's ROM</a>" field of the PCI Header in <a href="#PCI_Rev_Level_Byte_Order">Big-Endian byte-order</a>, rather than "Little-Endian" as per the general PCI Standard convention. (This flag does not affect any other field of the PCI Header). Initially disabled.<br> </div> <ul> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;"><a name="Ret_Stk_Interp"></a>Ret-Stk-Interp<br> </span></li> </ul> </ul> <div style="margin-left: 120px;">Allow Return-Stack Operations during Interpretation. While the Standard specifies that usage of the operators <span style="font-weight: bold; font-family: courier new,courier,monospace;">>r</span> <span style="font-weight: bold; font-family: courier new,courier,monospace;">r@</span> and <span style="font-weight: bold; font-family: courier new,courier,monospace;">r></span> while interpreting is allowed, actual practice in the industry is inconsistent. Developers who wish to take a more cautious approach to this question can disable this flag so that any attempt to use the operators <span style="font-weight: bold; font-family: courier new,courier,monospace;">>r</span> <span style="font-weight: bold; font-family: courier new,courier,monospace;">r@</span> and <span style="font-weight: bold; font-family: courier new,courier,monospace;">r></span> in the "interpreting" state will generate an <a href="#An_ERROR">ERROR</a> Message.<br> </div> <p style="margin-left: 40px;"> Also, the pseudo-Flag-name <span style="font-family: courier new,courier,monospace; font-weight: bold;">help</span> will cause a list of the Flag-names and their associated Special-Features to be printed.</p> <p style="margin-left: 40px;"> The use of some of these flags is illustrated in <a href="#Example_2">Example #2</a> </p> <h3><a class="mozTocH3" name="mozTocId445349"></a><a name="Tokenizer-Escape_Mode_"></a>“Tokenizer-Escape” Mode</h3> <p>The directive <span style="font-family: courier new,courier,monospace; font-weight: bold;">tokenizer[</span> behaves as specified in Section C.3.1 of the IEEE-1275 Standard: it saves the current tokenizer numeric conversion radix, sets the radix to sixteen (hexadecimal) and enters “tokenizer-escape” mode. Likewise, the directive <span style="font-family: courier new,courier,monospace; font-weight: bold;">]tokenizer</span> restores the radix and resumes the Tokenizer’s normal behavior.</p> <p> For convenience and compatibility with IBM's source-base, the directives <span style="font-family: courier new,courier,monospace; font-weight: bold;">f[ </span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">f]</span> are synonyms for <span style="font-family: courier new,courier,monospace; font-weight: bold;">tokenizer[</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">]tokenizer</span> respectively. In addition, the variant <span style="font-family: courier new,courier,monospace; font-weight: bold;">]f</span> is a synonym for <span style="font-family: courier new,courier,monospace; font-weight: bold;">f]</span> . </p> <p>The numeric conversion radix can be changed during “Tokenizer-Escape” mode by the use of the standard directives <span style="font-family: courier new,courier,monospace; font-weight: bold;">hex decimal </span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;"> octal</span> . These will always change the numeric conversion radix in “tokenizer-escape” mode; even if “tokenizer-escape” mode was entered in the middle of a colon-definition, they will not issue an FCode sequence. And, as per the Standard, the numeric conversion radix will be restored when the Tokenizer returns to "Normal" mode.<br> </p> <a name="Tkz_Esc_Scope"></a>Function-names that were defined during normal tokenization mode will not be recognized in “Tokenizer-escape” mode and vice-versa. The one exception is that <a href="#F_B-T-B_TkzEsc"><span style="font-family: courier new; font-weight: bold;">F[']</span></a> , even when invoked in “Tokenizer-escape” mode, will apply to function-names that were defined during normal tokenization mode.<br> <h4 style="margin-left: 40px;"><a name="mozTocId445715"></a>The <span style="font-family: courier new,courier,monospace;"><a name="emit_byte"></a>emit-byte</span> command </h4> <p style="margin-left: 40px;"><a name="Run-time_data_stack"></a>This Tokenizer supports the <span style="font-family: courier new,courier,monospace; font-weight: bold;">emit-byte</span> command as specified in the Section cited above. In order to be able to do that, the “tokenizer-escape” mode needs to be able to support a tokenization-time data stack, and, indeed, it does.<br> </p> <h4 style="margin-left: 40px;"><a name="mozTocId446081"></a>Other commands</h4> <p style="margin-left: 40px;">In “tokenizer-escape” mode, a string representing a number (optionally preceded by one of the directives <span style="font-family: courier new,courier,monospace; font-weight: bold;">h# d#</span> or <span style="font-family: courier new,courier,monospace; font-weight: bold;"> o#</span> ) causes that number to be pushed to the stack, where it is available for use by any of several other commands as follows:<br> </p> <h5 style="font-weight: bold; margin-left: 80px;"><big><a name="mozTocId446447"></a>Standard Commands</big></h5> <ul style="margin-left: 120px;"> <li><a name="mozTocId446813"></a>The <span style="font-family: courier new,courier,monospace; font-weight: bold;"><a name="next_fcode"></a>next-fcode</span> command </li> </ul> <div style="margin-left: 160px;">Set the value of the FCode-token-number assignment counter to the number that was on the stack. Subsequent fcode-functions defined in the source will be assigned FCode token numbers starting with this number. If the number supplied on the stack is outside the legal range specified by the IEEE-1275 Standard, the attempt will be disallowed and reported as an <a href="#An_ERROR">Error</a>.<br> <p>Note that this Tokenizer supports additional directives for <a href="#Manipulate_FCode_Number">manipulating the FCode-token-number assignment counter</a>.<br> </p> </div> <h5 style="margin-left: 80px;"><big><a name="mozTocId447179"></a>Non-Standard operations </big></h5> <ul style="margin-left: 120px;"> <li><span style="font-family: courier new,courier,monospace;"><span style="font-weight: bold;"><a name="Tkz_Esc_Const"></a><a name="mozTocId447545"></a>constant</span> <Name></span><br> </li> </ul> <p style="margin-left: 160px;">Define <span style="font-family: courier new,courier,monospace;"><Name></span> as a named constant with the value that was on the stack. <span style="font-family: courier new,courier,monospace;"><Name></span> will be known within “tokenizer-escape” mode but will not be recognized during normal tokenization. When <span style="font-family: courier new,courier,monospace;"><Name></span> is invoked, its value will be pushed onto the stack. Two named constants are pre-defined: <span style="font-family: courier new,courier,monospace; font-weight: bold;">true</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;"> false</span><br> </p> <ul style="font-family: courier new,courier,monospace; margin-left: 120px;"> <li><a name="emit_fcode"></a><span style="font-family: courier new,courier,monospace; font-weight: bold;"><a name="mozTocId447911"></a>emit-fcode</span></li> </ul> <p style="margin-left: 160px;">Emit the value that was on the stack as an FCode token, either one or two bytes long, depending on the value. Report an <a href="#An_ERROR">Error</a> if the number supplied on the stack is outside the legal range specified by the IEEE-1275 Standard. Since this is sort of a "cheat", issue an <a href="#Advisories">Advisory</a> if the operation is successful.<br> </p> <h4 style="margin-left: 40px;"><a name="mozTocId448277"></a>Additional FORTH-compatible operations</h4> <p style="margin-left: 40px;"> In addition to the above, “Tokenizer-escape” mode recognizes a limited number of FORTH-compatible named constants and operations, as follows:<br> </p> <ul style="margin-left: 40px;"> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">TRUE</span> Push -1 onto the stack </li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">FALSE</span> Push 0 onto the stack</li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">0=</span> Invert the Boolean-flag on top of the stack: replace 0 with <span style="font-family: courier new,courier,monospace;">TRUE</span> or any non-zero number with <span style="font-family: courier new,courier,monospace;">FALSE</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">SWAP</span> Exchange top two stack items</li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">2SWAP</span> Exchange top two pairs of stack items</li> <li><span style="font-weight: bold; font-family: courier new,courier,monospace;">noop</span> Take no action. </li> </ul> <p style="margin-left: 40px;">These are different from the corresponding words in "Normal" mode, which would compile an FCode token. In “Tokenizer-escape” mode, they initiate an immediate action within the Tokenization process. </p> <h3><a class="mozTocH3" name="mozTocId649525"></a><a name="Directives_"></a>Directives</h3> <p>This Tokenizer supports a number of directives that are not specified by the Standard, but which serve functions as follows:<br> </p> <ul> <li><a href="#Conditional_Tokenization">Conditional Tokenization</a></li> <li><a href="#The_OVERLOAD_Directive">Suspending</a> the Duplicate-Name Test for one Definition ("Overloading")</li> <li>Suspending the <a href="#Allow_Multi_Line">Multi-Line Warning</a> for one occasion<br> </li> <li><a href="#mozTocId203416">Controlling the Scope of Definitions</a></li> <li><a href="#Evaluating_Command-line_Symbols">Evaluation</a> of symbols defined on the command-line</li> <li>Outputting <a href="#FLITERAL">arbitrary sequences</a> of bytes to the FCode binary file</li> <li><a href="#ENCODE_FILE">Encoding</a> blocks of binary data taken from a file</li> <li>Generating <a href="#Gen_Specl_Txt_Strs">Special Text-Strings</a> and Literals: <br> </li> <ul> <li>The <a href="#fcode_date">current date or time</a>.</li> <li>The <a href="#function_name">name of the function</a> currently being defined</li> <li>The <a href="#Inp_Fil_Nm_Strg">Input-File Name</a> and Line Number <br> </li> </ul> <li>Pre-pending <a href="#Pre_pending_PCI_Headers_to_FCode_images_">PCI headers</a> to FCode images</li> <li><a href="#Modifying_PCI_Header">Modifying</a> the PCI Header<br> </li> <li>Changing the name of the <a href="#Binary_Output_File_Name">Binary Output File</a></li> <li>Issuing a <a href="#User_Messages">message</a> at tokenization time</li> <li><a href="#Changing_C-L_Flags_from_Source">Over-riding</a> the setting of a <a href="#Special_Feature_Flags">Special-Feature Flag</a></li> <li><a href="#Displaying_C-L_Flags_from_Source">Displaying</a> the settings of all the <a href="#Special_Feature_Flags">Special-Feature Flags</a> </li> <li><a href="#Manipulate_FCode_Number">Saving, Restoring and Resetting the FCode-Token-Number Assignment Counter</a> </li> <li><a href="#Resetting_Symbols_Defined_in_Either_Mode">Resetting the symbols</a> defined either in Normal Tokenization Mode or in "Tokenizer Escape" mode.<br> </li> </ul> <h4><a class="mozTocH4" name="mozTocId557512"></a><a name="Conditional_Tokenization"></a>Conditional Tokenization</h4> The OpenBIOS Tokenizer toke supports a fully-nestable Conditional Tokenization capability comparable to the one in the "<big><b>C</b></big>" pre-processor. A Conditional Tokenization block consists of either one or two segments -- a "True" segment and an optional "False" segment -- delimited by <a name="Conditional_Operators"></a>Conditional Operators of three types:<br> <ul> <li>the <a href="#Condition_Testers">Condition-Tester</a></li> <li>the optional <a href="#The_False_segment-switcher">"False" segment switcher</a></li> <li>the <a href="#The_Conditional-block_Terminator">Conditional-block terminator</a></li> </ul> <p>The "True" segment immediately follows the Condition-Tester, and is ended either by the "False" segment switcher or by the Conditional-block terminator. If the "False" segment switcher is present, it introduces the "False" segment, which is ended by the Conditional-block terminator. The three delimiters (in reverse order) are: </p> <h5 style="margin-left: 40px;"><a class="mozTocH5" name="mozTocId686605"></a><a name="The_Conditional-block_Terminator"></a><big>The Conditional-block Terminator</big></h5> <div style="margin-left: 40px;">Exit the current level of Conditional Tokenization. <p>If the Conditional-block in question was nested within another one, resume conditional processing at the level of the enclosing segment. When the outermost Conditional-block is exited, resume normal processing.<br> </p> <p>While it is a requirement that the Conditional-block terminator be contained within the same Input File as the Condition-Tester and its optional "False" segment switcher, the body of a Conditional Segment may contain separate <span style="font-family: courier new,courier,monospace; font-weight: bold;">fload</span> directives, which will be processed or ignored in accordance with the prevailing Condition. An <a href="#Example_4_Condl_FLoad">illustration</a> can be seen in <a href="#Example_4">Example #4</a>. </p> There are several synonyms for the Conditional-block terminator:<br> </div> <ul style="margin-left: 40px;"> <big> </big><li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[then]</span></li> <big> </big><li><span style="font-family: courier new,courier,monospace; font-weight: bold;">#then</span></li> <big> </big><li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[#then]</span></li> <big> </big><li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[endif]</span></li> <big> </big><li><span style="font-family: courier new,courier,monospace; font-weight: bold;">#endif</span></li> <big> </big><li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[#endif]</span></li> </ul> <h5 style="margin-left: 40px;"><a class="mozTocH5" name="mozTocId763728"></a><a name="The_False_segment-switcher"></a><big>The "False" segment-switcher</big></h5> <p style="margin-left: 40px;">Reverses the sense of the condition and introduces the "False" segment.</p> <p style="margin-left: 40px;">If the Condition-Test resulted in "TRUE", then the first segment -- the "True" segment -- was processed and the "False" segment will be ignored. Conversely, if the Condition-Test resulted in "FALSE", then the first segment -- the "True" segment -- was ignored and the "False" segment will be processed.</p> <p style="margin-left: 40px;">There are three synonyms for this function:<br> </p> <ul style="margin-left: 40px;"> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[else]</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">#else</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[#else]</span></li> </ul> <h5 style="margin-left: 40px;"><a class="mozTocH5" name="mozTocId375310"></a><a name="Condition_Testers"></a><big>Condition-Testers</big></h5> <div style="margin-left: 40px;">Tokenization can be controlled according to the following conditions: </div> <ul style="margin-left: 40px;"> <li>A <a href="#TrueFalse_flag_on_the_top_of_the_stack">True/False flag</a> on the top of the stack</li> <li><a href="#Existence_or_non-existence_of_an_FCode">Existence</a> or non-existence of an FCode or "Tokenizer Escape"-mode definition</li> <li><a href="#Definition_or_non-definition_of_a">Definition</a> or non-definition of a Command-Line symbol.</li> </ul> <h5 style="margin-left: 80px;"><a class="mozTocH5" name="mozTocId104560"></a><a name="TrueFalse_flag_on_the_top_of_the_stack"></a><big>True/False flag on the top of the stack</big></h5> <div style="margin-left: 80px;"> <p>A number that was placed on the stack in “Tokenizer-Escape” mode will be consumed and tested. If the number was non-zero, the Condition-Test will result in "TRUE", and the first segment -- the "True" segment -- will be processed and the "False" segment, if present, will be ignored. Conversely, if the number was zero, the Condition-Test will result in "FALSE", and the first segment -- the "True" segment -- will be ignored and the "False" segment, if present, will be processed.</p> <p>There is only one word for this function:<br> </p> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[if]</span></li> </ul> The <span style="font-family: courier new,courier,monospace; font-weight: bold;">[if]</span> Operator can be invoked from either "Tokenizer Escape" mode or normal tokenization mode, but the number to be tested must have been put on top of the Stack during "Tokenizer Escape" mode. </div> <h5 style="margin-left: 80px;"><a class="mozTocH5" name="mozTocId956359"></a><a name="Existence_or_non-existence_of_an_FCode"></a><big>Existence or non-existence of an FCode or "Tokenizer Escape"-mode definition</big></h5> <p style="margin-left: 80px;">A name-string must follow the directive <a href="#Expected_on_same_line">on the same line</a>. A search for that name is conducted through the word-list of the mode -- i.e., "Tokenizer Escape" mode versus "Normal" mode -- and the <a href="#Scope_Directives">Scope</a> -- i.e., "<a href="#Global_Definitions">Global</a>" versus "<a href="#device-node_vocabularies">Current Device-Node</a>" -- in which the Tokenizer is currently operating.</p> <p style="margin-left: 80px;">If the directive is for the existence of the definition, and the name is found, or if the directive is for the non-existence of the definition, and the name is not found, the Condition-Test will result in "TRUE". Otherwise, the Condition-Test results in "FALSE".</p> <div style="margin-left: 80px;">The synonyms for the test for <span style="font-style: italic; font-weight: bold;">existence</span> of a definition are:<br> </div> <ul style="margin-left: 80px;"> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[ifexist]</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">#ifexist</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[#ifexist]</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[ifexists]</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">#ifexists</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[#ifexists]</span></li> </ul> <p style="margin-left: 120px;">(Note the variants with and without a final '<span style="font-weight: bold;">s</span>')<br> </p> <div style="margin-left: 80px;">The synonyms for the test for <span style="font-weight: bold; font-style: italic;">non-existence</span> of a definition are:<br> </div> <ul style="margin-left: 80px;"> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[ifnexist]</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">#ifnexist</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[#ifnexist]</span></li> </ul> <div style="margin-left: 120px;">(Note that variants with a final '<span style="font-weight: bold;">s</span>' didn't make sense here.)<br> </div> <h5 style="margin-left: 80px;"><a class="mozTocH5" name="mozTocId880808"></a><a name="Definition_or_non-definition_of_a"></a><big>Definition or non-definition of a Command-Line Symbol</big></h5> <div style="margin-left: 80px;">As noted <a href="#Define_Command-Line_symbol">above</a>, the Tokenizer recognizes the syntax<br> </div> <div style="margin-left: 120px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">-d Symbol</span>[<span style="font-family: courier new,courier,monospace; font-weight: bold;">=Value</span>] <br> </div> <div style="margin-left: 80px;">as the means by which to define a Command-Line Symbol and optionally assign a value to it.<br> </div> <div style="margin-left: 80px;"> <p>A pair of Condition-Tester directives are supported that will test, respectively, for definition or non-definition of a named Symbol. Their operation is similar to that of the Tests for existence of non-existence of a Definition, in that a name-string must follow the directive <a href="#Expected_on_same_line">on the same line</a>, but they are different in the matter of where the search for the name string is conducted: these directives search the list of Command-Line Symbols. The relation between the type of directive and the result of the search is also similar to that of the Tests for existence of non-existence of a Definition.</p> </div> <div style="margin-left: 80px;">The synonyms for the test for <span style="font-weight: bold; font-style: italic;">definition</span> of a Command-Line Symbol are:<br> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[ifdef]</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">#ifdef</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[#ifdef]</span></li> </ul> </div> <div style="margin-left: 80px;">The synonyms for the test for <span style="font-weight: bold; font-style: italic;">non-definition</span> of a Command-Line Symbol are:<br> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[ifndef]</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">#ifndef</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[#ifndef]</span><span style="font-family: courier new,courier,monospace; font-weight: bold;"></span> </li> </ul> </div> <div style="margin-left: 80px;">The test is simply to verify the existence of a Symbol; it is not sensitive to whether or not the optional value was assigned. <br> </div> <h5 style="margin-left: 40px;"><a name="mozTocId891224"></a><a name="Tracing_Conditional_State"></a><big>Tracing the state of Conditional Tokenization</big></h5> <div style="margin-left: 40px;">The nesting and un-nesting of <a href="#Conditional_Tokenization">Conditional Tokenization</a> can become complicated; an <span style="font-family: courier new,courier,monospace; font-weight: bold;">fload</span>ed file may contain a segment-switcher or Conditional-block terminator that interacts with the prevailing Condition-Tester that originated in another Source file, which might lead to unexpected results. To help trace the status of Conditional Tokenization, the User can invoke the <a href="#Trace_Condls"><span style="font-family: courier new,courier,monospace; font-weight: bold;">Trace-Conditionals</span></a> Special-Feature Flag together with the"verbose" option ( <a href="#verbose_option"><span style="font-weight: bold; font-family: courier new,courier,monospace;">-v</span></a> ). This will cause an <a href="#Advisories">Advisory Message</a> to be displayed whenever a <a href="#Conditional_Operators">Conditional Operator</a> is encountered, even if it is in a segment that is already being ignored. The message will indicate the location of the associated <a href="#Condition_Testers">Condition-Tester</a> (or the state of the condition, if the Conditional Operator <span style="font-style: italic;">is</span> a Condition-Tester) and whether the segment is being Processed or being Ignored. </div> <br> <h4><a class="mozTocH4" name="mozTocId202222"></a><a name="The_OVERLOAD_Directive"></a><big>Suspending the Duplicate-Name Test for one Definition ("Overloading")</big></h4> <p>When a definition is created whose name duplicates that of an existing definition, default behavior is to issue a <a href="#A_WARNING">WARNING</a> notification. </p> <p>Intentionally creating such a duplicately-named definition is called "overloading" the name. This may be required, for instance, to supplant future invocations of the named function with a version that incorporates the earlier instance of the function of the same name and supplies additional behavior. </p> <p>When this is intentional, no warning should be issued. This Tokenizer supports a directive called <span style="font-family: courier new,courier,monospace; font-weight: bold;">overload</span> which the User may invoke to bypass the duplicate-name test for the duration of only one definition that follows it (as contrasted with <a href="#Warn_if_Duplicate_Flag">suspending the test globally</a>). An illustration of its use may be seen in <a href="#Example_4">Example 4</a>.<br> </p> <h4><a class="mozTocH4" name="mozTocId202620"></a><a name="Allow_Multi_Line"></a><big>Suspending the Multi-Line Warning for one occasion</big></h4> <p>The Standard allows Comments and Strings that extend across multiple lines, terminated by their specific delimiter. In addition, this Tokenizer allows User-generated Messages and Local-Values Declarations that, likewise, extend across multiple lines. Because of the potential for a cascade of errors that can be caused by a missing delimiter, this Tokenizer issues a <a href="#A_WARNING">WARNING</a> notification whenever such an entity is encountered. <a href="#Example_5_func_nam">Example #5</a> shows an occasion where this might be helpful.<br> </p> <p>When this is intentional, no warning should be issued. This Tokenizer supports a directive called <span style="font-family: courier new,courier,monospace; font-weight: bold;">multi-line</span> which the User may invoke to suppress the notification for the next multi-line item that follows it. </p> <h4><a class="mozTocH4" name="mozTocId203416"></a><a name="Scope_Directives"></a><big>Controlling the Scope of Definitions</big></h4> <p>The User may wish to create a collection of utility functions that will be available to all the device-nodes in a <a href="#Multiple_device_nodes">multiple-node driver</a>. Directly accessing such functions across device-nodes can be risky if any component uses <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> data. However, if the use of <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> data is precluded, such access can be performed safely.</p> <p>This Tokenizer supports a pair of directives for setting the Scope of Definitions. The one called <span style="font-family: courier new,courier,monospace; font-weight: bold;">global-definitions</span> will cause all subsequent definitions -- Aliases and Macros as well as FCode -- to be entered into the same vocabulary -- referred to as the "core" -- from which all the Standard functions are drawn. The other, called <span style="font-family: courier new,courier,monospace; font-weight: bold;">device-definitions</span> , will cause the Scope of Definitions to revert to the <a href="#current_device-node"><span style="font-family: courier new,courier,monospace; font-style: italic;">current device-node</span></a>. The use of these directives is illustrated in <a href="#Example_4">Example #4</a>.<br> </p> <p>While Global Scope is in effect, the use of the word <a href="#Instance_Not_Allowed"><span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span></a> will not be allowed, nor will definitions made in any device-node be recognized. Conversely, an attempt to enter Global Scope while <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> is in effect will be reported as an <a href="#An_ERROR">Error</a> condition.</p> <h4><a class="mozTocH4" name="mozTocId314185"></a><a name="Evaluating_Command-line_Symbols"></a><big>Evaluating Command-line Symbols</big></h4> A Directive is supported that can be used to extract the <a href="#Define_Command-Line_symbol">optional value</a> that was assigned to a Command-Line Symbol. <p>The Symbol name must appear <a href="#Expected_on_same_line">on the same line</a> as the directive.</p> <p>If the Symbol name is not found or no value has been assigned to it, a <a href="#A_WARNING">WARNING</a> will be issued.</p> Otherwise, the associated value will be interpreted as though it were source-code. <p>The synonyms for the directive to evaluate a Command-Line Symbol's assigned value are:<br> </p> <ul> <li><span style="font-weight: bold; font-family: courier new,courier,monospace;">[defined]</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">#defined</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[#defined]</span></li> </ul> <h4><a class="mozTocH4" name="mozTocId655967"></a><big><a name="FLITERAL"></a>Outputting Arbitrary Byte-Sequences to the FCode Binary</big></h4> In addition to the Standard <span style="font-family: courier new,courier,monospace; font-weight: bold;">emit-byte</span> command, this Tokenizer supports a directive called <span style="font-family: courier new,courier,monospace; font-weight: bold;">FLITERAL</span> , which will emit the number popped from the top of the Data Stack as a literal to the FCode Binary, as though the number were invoked during normal operation. <p>The <span style="font-family: courier new,courier,monospace; font-weight: bold;">FLITERAL</span> directive can be invoked from either "Tokenizer Escape" mode or normal tokenization mode, but the number to be emitted must have been put on top of the Stack during "Tokenizer Escape" mode.</p> <h4><a class="mozTocH4" name="mozTocId114013"></a><big><a name="ENCODE_FILE"></a>Encoding blocks of binary data taken from a file </big></h4> The directive <span style="font-family: courier new,courier,monospace; font-weight: bold;">ENCODE-FILE</span> takes a file-name as an argument <a href="#Expected_on_same_line">on the same line</a>. It translates the contents of the file into a series of strings interspersed with <span style="font-family: courier new,courier,monospace; font-weight: bold;">encode-bytes</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">encode+</span> commands, resulting in a block of byte-encoded binary data.<br> <h4><a name="mozTocId69109"></a><big><a name="Gen_Specl_Txt_Strs"></a>Generating Special Text-Strings and Literals</big></h4> This Tokenizer supports a set of directives that will present a string or a literal for processing as though it were part of the Tokenization Source File. Except as otherwise noted, these directives may be invoked in either "Normal" or "Tokenizer-Escape" mode: in "Normal" mode, the string produced will be compiled-in as an in-line text string; in "Tokenizer-Escape" mode, it will be displayed as a User-generated <a href="#User_Messages"><span style="font-weight: bold; font-style: italic;">MESSAGE</span></a>.<br> <br> <h5 style="margin-left: 40px;"><a class="mozTocH4" name="mozTocId70133"></a><big><a name="fcode_date"></a>Current date or time</big></h5> <div style="margin-left: 40px;">The <span style="font-family: courier new,courier,monospace; font-weight: bold;">[fcode-date]</span> directive produces a string that consists of the current date, formatted as <span style="font-family: courier new,courier,monospace;">mm/dd/ccyy</span> . </div> <p style="margin-left: 40px;">The <span style="font-family: courier new,courier,monospace; font-weight: bold;">[fcode-time]</span> directive produces a string that consists of the current time, formatted as <span style="font-family: courier new,courier,monospace;">hh:mm:ss ZZZ</span> (where <span style="font-family: courier new,courier,monospace;">ZZZ</span> represents the local Time-Zone).<br> </p> <p style="margin-left: 40px;">An <a href="#timestamp_prop">illustration</a> is included in <a href="#Example_4">Example 4</a>.<br> </p> <h5 style="margin-left: 40px;"><a class="mozTocH4" name="mozTocId71157"></a><big><a name="function_name"></a>Name of the Function currently being defined</big></h5> <div style="margin-left: 40px;"> <p>The <span style="font-family: courier new,courier,monospace; font-weight: bold;">[function-name]</span> directive, when invoked in "Normal" mode, produces an in-line string that consists of the name of the function (colon-definition) most recently -- or currently being -- defined. It will persist until a new colon-definition is started. This can be useful for embedding interpetation-time or run-time debugging-statements into or after functions' definitions. In "Tokenizer-Escape" mode, it will display the function name in more detail as a User-generated <a href="#User_Messages"><span style="font-weight: bold; font-style: italic;">MESSAGE</span></a>. <a href="#Example_5">Example 5</a> illustrates its use in "Normal" mode, and has a small <a href="#Example_5_func_nam">illustration</a> of its use in "Tokenizer-Escape" mode. </p> </div> <h5 style="margin-left: 40px;"><a name="mozTocId72181"></a><big><a name="Inp_Fil_Nm_Strg"></a>Input-File Name and Line Number</big></h5> <div style="margin-left: 40px;">The <span style="font-family: courier new,courier,monospace; font-weight: bold;">[input-file-name]</span>directive produces an in-line string that consists of the name of the current Input File.<br> <p>The <span style="font-family: courier new,courier,monospace; font-weight: bold;">[line-number]</span>directive produces an in-line numeric literal giving the Line-Number within the current Input File.<br> </p> <p>These directives can only be invoked in "Normal" mode; they are not supported -- or needed -- in "Tokenizer-Escape" mode, because any User-generated <a href="#User_Messages"><span style="font-weight: bold; font-style: italic;">MESSAGE</span></a> will print that information. An <a href="#Example_5_func_nam">illustration</a> is included in <a href="#Example_5">Example 5</a>.<br> </p> </div> <h4><a class="mozTocH4" name="mozTocId844437"></a><big><a name="Pre_pending_PCI_Headers_to_FCode_images_"></a>Pre-pending PCI Headers to FCode images</big> </h4> The directive <span style="font-family: courier new,courier,monospace; font-weight: bold;">pci-header</span> , which can be invoked from either "Tokenizer Escape" mode or normal tokenization mode, will cause a PCI Header to be generated to the Binary Output file, in front of the FCode Binary image. It takes three parameters from the Data Stack: Vendor ID as the third item on the Stack, Device ID as the second, and Class Code as the top item on the Data Stack. These must be put on the Stack during "Tokenizer Escape" mode. <p>An attempt to issue the <span style="font-family: courier new,courier,monospace; font-weight: bold;">pci-header</span> directive after FCode output has begun will be reported as an <a href="#An_ERROR">Error</a> condition.</p> <p> The PCI Header cannot be completed until after the FCode Binary image has been completely tokenized. The directive to complete the PCI Header should be issued at the end of the process. Synonyms for this directive are: </p> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">pci-header-end</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">pci-end</span></li> </ul> <h4 style="font-weight: bold;"><a class="mozTocH4" name="mozTocId931658"></a><a name="Modifying_PCI_Header"></a><big>Modifying the PCI Header</big></h4> Directives are supported that will alter specific fields of the PCI Header. They can be issued at any time before the <span style="font-family: courier new,courier,monospace; font-weight: bold;">pci-end</span> directive to specify the contents of certain fields of the PCI Data Structure as follows:<br> <ul> <li>"Revision Level of the Vendor's ROM" (2 bytes at offset 0x12)</li> <li>"Last Image Indicator" bit (High-order bit of 1 byte at offset 0x15)</li> </ul> The syntax for these functions is:<br> <h5 style="margin-left: 40px;"><a class="mozTocH5" name="mozTocId504353"></a><big><a name="PCI_Rev_Level"></a>"Revision Level of the Vendor's ROM"</big></h5> <div style="margin-left: 40px;">To set the "Revision Level of the Vendor's ROM" field of the PCI Header to the number popped from the top of the Data Stack, use any of these synonyms:<br> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">set-rev-level</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">pci-revision</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">pci-code-revision</span></li> </ul> These directives can be invoked from either "Tokenizer Escape" mode or normal tokenization mode, but the number to be used must have been put on top of the Stack during "Tokenizer Escape" mode. <p>The default setting for this field is 1.<br> </p> <h6 style="font-weight: bold; margin-left: 40px;"><a name="mozTocId503878"></a><big><a name="PCI_Rev_Level_Byte_Order"></a>Byte-Order</big></h6> <p style="margin-left: 40px;">Ordinarily, the "Revision Level of the Vendor's ROM" field of the PCI Header follows the general PCI Standard convention of "Little-Endian" byte-order. However, some organizations' legacy code saves this field in Big-Endian order. To accommodate the need for compatibility, this Tokenizer supports a <a href="#Special_Feature_Flags">Special-Feature Flag</a> called <a href="#Big_End_PCI_Rev_Level"><span style="font-family: courier new,courier,monospace; font-weight: bold;">Big-End-PCI-Rev-Level</span></a>. Its default is <span style="font-family: courier new,courier,monospace; font-weight: bold;">no</span>, i.e., to follow the PCI Standard. </p> <br> </div> <h5 style="margin-left: 40px;"><a class="mozTocH5" name="mozTocId53081"></a><big><a name="Last_Image_Indicator_bit"></a>"Last Image Indicator" bit</big></h5> <div style="margin-left: 40px;">The "Last Image Indicator" bit can be specified in either of three ways:<br> <ul> <li>Force it to be set to TRUE. Synonyms for this are:</li> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">last-image</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">last-img</span></li> </ul> </ul> <ul> <li>Force it to be reset to FALSE. Synonyms for this are:</li> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">not-last-image</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">not-last-img</span></li> </ul> </ul> <ul> <li>Set or reset it according to the number popped from the top of the Data Stack. Synonyms for this are:</li> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">set-last-image</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">set-last-img</span></li> </ul> </ul> </div> <div style="margin-left: 80px;">If the number was zero, the "Last Image Indicator" bit will be reset to FALSE; if it was non-zero, the bit will be set to TRUE.</div> <p style="margin-left: 80px;">These directives can be invoked from either "Tokenizer Escape" mode or normal tokenization mode, but the number to be examined must have been put on top of the Stack during "Tokenizer Escape" mode. </p> <p style="margin-left: 40px;">The default setting for this field is TRUE.</p> <h4><a class="mozTocH4" name="mozTocId410469"></a><big><a name="Binary_Output_File_Name"></a>Changing the name of the Binary Output File</big></h4> <p><a name="Binary_Output_File_Name_Default"></a>By default, the name of the Binary Output File is derived from the name of the Source Input File, by replacing its extension with <span style="font-family: courier new,courier,monospace; font-weight: bold;">.fc</span> , or, if the Input File name had no extension, merely appending the extension <span style="font-family: courier new,courier,monospace; font-weight: bold;">.fc</span></p> <p> The name of the Binary Output File may be specified on the Command Line, as noted <a href="#Binary_Output_Name_option">above</a>.</p> <p><a name="Binary_Output_File_Name_Directive"></a> The name of the Binary Output File may also be specified by a directive embedded within the Tokenization Source File. Synonyms for the directive are <span style="font-family: courier new,courier,monospace; font-weight: bold;">save-image</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">save-img</span> ; the name follows after the directive <a href="#Expected_on_same_line">on the same line</a>.<br> </p> <p>The directive can be invoked from either "Tokenizer Escape" mode or normal tokenization mode. It does not cause an imediate action (i.e., saving the Binary Image), but merely alters the name of the file to which the image will be saved when tokenization is completed.<br> </p> <p>Note that this directive does not change the name of the <a href="#FLoad_List_option">FLoad-List File</a>, if one has been specified. </p> <h4><a class="mozTocH4" name="mozTocId982642"></a><big><a name="User_Messages"></a>Issuing messages at Tokenization time.</big></h4> Directives are supported that will gather text and output it as a User-generated <span style="font-weight: bold; font-style: italic;">MESSAGE</span> during Tokenization. <p>These directives can be invoked from either "Tokenizer Escape" mode or normal tokenization mode:</p> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">#MESSAGE"</span> will parse text in <a href="#String_Gathering_Features">string-collection mode</a>, i.e., with sensitivity to the special escaped-characters, until a concluding Quote-followed-by-whitespace,</li> </ul> <div style="margin-left: 40px;">and the synonyms: </div> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[MESSAGE]</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">#MESSAGE</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[#MESSAGE]</span></li> </ul> <div style="margin-left: 40px;">will gather the text remaining on the line. </div> <p>In addition, the commands <span style="font-family: courier new,courier,monospace; font-weight: bold;">."</span> (Dot-Quote) and <span style="font-family: courier new,courier,monospace; font-weight: bold;">.(</span> (Dot-Paren), which have Standard meanings in normal tokenization mode, will, when invoked in "Tokenizer Escape" mode, collect text in their Standard manner and output it as a User-generated <span style="font-weight: bold; font-style: italic;">MESSAGE</span>:</p> <ul> <li>Dot-Quote will parse text in <a href="#String_Gathering_Features">string-collection mode</a>,</li> <li>Dot-Paren will collect text until a balancing Close-Paren -- <span style="font-family: courier new,courier,monospace; font-weight: bold;">)</span> -- character.</li> </ul> <p>Also, as noted earlier, the <a href="#fcode_date"><span style="font-family: courier new,courier,monospace; font-weight: bold;">[fcode-date]</span></a> and <a href="#fcode_date"><span style="font-family: courier new,courier,monospace; font-weight: bold;">[fcode-time]</span></a> directives, when invoked in "Tokenizer Escape" mode, will display the current date and time, respectively, as a User-generated <span style="font-weight: bold; font-style: italic;">MESSAGE</span>: </p> <h4><a class="mozTocH4" name="mozTocId550942"></a><big><a name="Changing_C-L_Flags_from_Source"></a>Changing Special-Feature Flags from Source</big></h4> A directive is supported that can be used from within the Tokenization Source File to over-ride the setting of any one of the <a href="#Special_Feature_Flags">Special-Feature Flags</a> that might have been made from the Command Line. The name of the Flag -- with, of course, an optional leading <span style="font-family: courier new,courier,monospace; font-weight: bold;">No</span> -- must follow after the directive <a href="#Expected_on_same_line">on the same line</a>. It can be invoked from either "Tokenizer Escape" mode or normal tokenization mode. Its synonyms are: <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[FLAG]</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">#FLAG</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[#FLAG]</span></li> </ul> <p>The User is hereby admonished to exercise caution when using this directive. Not all combinations are meaningful, and automated error-checking is not feasible. An <a href="#Advisories">Advisory Message</a> will be issued to remind the User of the change.<br> </p> <h5 style="margin-left: 40px;"><a class="mozTocH5" name="mozTocId551846"></a><big><a name="Displaying_C-L_Flags_from_Source"></a>Displaying Special-Feature Flags from Source</big></h5> <div style="margin-left: 40px;">A directive is supported that can be used from within the Tokenization Source File to display a <a href="#User_Messages"><span style="font-weight: bold; font-style: italic;">MESSAGE</span></a> with a list of the settings of all of the Special-Feature Flags. Its synonyms are: </div> <div style="margin-left: 40px;"> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[FLAGS]</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">#FLAGS</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">[#FLAGS]</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">SHOW-FLAGS</span></li> </ul> </div> <h4><a class="mozTocH4" name="mozTocId573280"></a><big><a name="Manipulate_FCode_Number"></a>Manipulating the FCode-Token-Number Assignment Counter</big></h4> In addition to the Standard <a href="#next_fcode"><span style="font-family: courier new,courier,monospace; font-weight: bold;">next-fcode</span></a> command, this Tokenizer supports additional directives that can be used to alter the normal sequence of FCode-token-number assignment.<br> <p>In order to protect against unintended collisions in FCode-token numbers, which can cause severe errors at run-time, this Tokenizer will report an <a href="#An_ERROR">Error</a> the first time an FCode-number assignment overlaps FCodes that were assigned in a different range.<br> </p> <p>Because the programmer may choose to "recycle" FCode-token-numbers intentionally, a directive is supported that clears the records of FCode-number assignments and resets the FCode-token-number assignment counter to its inital value. </p> <h5 style="margin-left: 40px;"><big><a name="mozTocId566072"></a>Saving and Restoring</big></h5> <div style="margin-left: 40px;"> The directive <span style="font-family: courier new,courier,monospace; font-weight: bold;">FCode-Push</span> can be used to save the value of the FCode-token-number assignment counter on the <a href="#Run-time_data_stack">tokenization-time data stack</a> . Later, the saved value can be restored by invoking the <span style="font-family: courier new,courier,monospace; font-weight: bold;">FCode-Pop</span> directive. Note that <span style="font-family: courier new,courier,monospace; font-weight: bold;">FCode-Pop</span> is functionally equivalent to <a href="#next_fcode"><span style="font-family: courier new,courier,monospace; font-weight: bold;">next-fcode</span></a> except that <span style="font-family: courier new,courier,monospace; font-weight: bold;">FCode-Push</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">FCode-Pop</span> can be invoked from either "Tokenizer Escape" mode or "Normal" mode.</div> <h5 style="margin-left: 40px;"><big><a name="mozTocId568474"></a>Resetting</big></h5> <div style="margin-left: 40px;"> The directive <span style="font-family: courier new,courier,monospace; font-weight: bold;">FCode-Reset</span> will re-initalize the value of the FCode-token-number assignment counter and clear the records of previous FCode-number assignments. Note that it is not equivalent to:<br> <p style="margin-left: 40px;"><span style="font-weight: bold; font-family: courier new,courier,monospace;">F[</span> <span style="font-weight: bold; font-family: courier new,courier,monospace;">h# 800 next-fcode</span> <span style="font-weight: bold; font-family: courier new,courier,monospace;">F]</span></p> which merely re-initalizes the value of the FCode-token-number assignment counter, but does not prevent the first assignment of this FCode-number from being regarded as overlapping an earlier assignment and therefore being reported as an <a href="#An_ERROR">Error</a>.<br> <p>The FCode-token-number assignment counter and the records of previous FCode-number assignments will also be automatically re-initalized when a <a href="#Multiple_PCI_Image">new PCI-Image</a> block is started.<br> </p> </div> <h4><a class="mozTocH4" name="mozTocId575686"></a><big>Resetting Symbols Defined in Either Mode</big></h4> Symbol names defined in "Normal" mode persist until a <a href="#Multiple_device_nodes">device-node is finished</a>, or until the end of an FCode-block or of a PCI Image.<br> <p>Symbol names defined in "Tokenizer Escape" mode persist throughout the entire run of the Tokenizer. </p> The directive <span style="font-family: courier new,courier,monospace; font-weight: bold;">Reset-Symbols</span> enables the User to delete symbol-definitions at any other time, should that be required. <span style="font-family: courier new,courier,monospace; font-weight: bold;">Reset-Symbols</span> is sensitive to the the mode in which the Tokenizer is operating: invoked during "Tokenizer Escape" mode, it will cause only the definitions made under "Tokenizer Escape" mode to be deleted; during "Normal" mode, only those made under "Normal" mode. <a href="#Example_1">Example #1</a> contains an invocation in "Tokenizer Escape" mode.<br> <br> <h3><a class="mozTocH3" name="mozTocId957252"></a><a name="Non-standard_input_syntaxes_"></a>Non-standard input, syntaxes, and behavior<br> </h3> <p>In this section, we will discuss:<br> </p> <ul> <li>This Tokenizer's handling of conditions the Standard calls "ambiguous"</li> <li>Non-Standard synonyms for Standard functions</li> <li>Non-Standard functions or behaviors that are supported by this Tokenizer.</li> <li>Featured behaviors, supported by this Tokenizer, that are not mentioned in the Standard. </li> </ul> <h4 style="margin-left: 40px;"><a class="mozTocH4" name="mozTocId850914"></a>Ambiguous Conditions</h4> <div style="margin-left: 80px;">The Standard only identifies a few questionable combinations as "ambiguous conditions" or "behavior ... unspecified" and leaves their handling open to interpretation of the implementor. Here's how this Tokenizer handles them:<br> </div> <div style="margin-left: 40px;"> <h5 style="margin-left: 40px;"><a class="mozTocH5" name="mozTocId162252"></a><big><a name="Expected_on_same_line"></a>Tokens expected on the same line</big></h5> <p style="margin-left: 40px;">Certain commands and directives expect a token to appear on the same line, and will report an <a href="#An_ERROR">Error</a> condition if no token appears on the same line:</p> <ul> <ul> <li>The <a href="#The_h_d_and_o_directives_"><span style="font-family: courier new,courier,monospace; font-weight: bold;">h#</span> <span style="font-family: courier new,courier,monospace; font-weight: bold;">d#</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">o#</span></a> directives, and the <a href="#Char_Seq_To_Num">a#</a> and <a href="#Char_to_Num_Left_Justified">al#</a> directives.<br> </li> <li>The <a href="#Existence_or_non-existence_of_an_FCode"><span style="font-family: courier new,courier,monospace; font-weight: bold;">[ifexist]</span> <span style="font-family: courier new,courier,monospace; font-weight: bold;">[ifnexist]</span></a> <a href="#Definition_or_non-definition_of_a"><span style="font-family: courier new,courier,monospace; font-weight: bold;">[ifdef]</span> <span style="font-family: courier new,courier,monospace; font-weight: bold;">[ifndef]</span></a> and <a href="#Evaluating_Command-line_Symbols"><span style="font-family: courier new,courier,monospace; font-weight: bold;">[defined]</span></a> directives and all their synonyms</li> <li>The commands <span style="font-family: courier new,courier,monospace; font-weight: bold;">[']</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">'</span> <br> </li> <li>The <a href="#F_Eff-Bracket-Tick-Bracket"><span style="font-family: courier new,courier,monospace; font-weight: bold;">F[']</span></a> directive</li> <li>The <a href="#Alias"><span style="font-family: courier new,courier,monospace; font-weight: bold;">ALIAS</span></a> directive (expects two tokens on the same line)</li> <li>The <a href="#Macros"><span style="font-family: courier new,courier,monospace; font-weight: bold;">[macro]</span></a> directive (expects at least two tokens on the same line) </li> <li>The directives <span style="font-family: courier new,courier,monospace; font-weight: bold;">control ascii </span><span style="font-family: courier new,courier,monospace; font-weight: bold;">char</span><span style="font-family: courier new,courier,monospace; font-weight: bold;"> </span>and<span style="font-family: courier new,courier,monospace; font-weight: bold;"> [char]</span></li> <li>The <span style="font-family: courier new,courier,monospace; font-weight: bold;">FLOAD</span> command</li> <li>The <a href="#Binary_Output_File_Name"><span style="font-family: courier new,courier,monospace; font-weight: bold;">SAVE-IMAGE</span></a> directive</li> <li>The <a href="#Changing_C-L_Flags_from_Source"><span style="font-family: courier new,courier,monospace; font-weight: bold;">[FLAG]</span></a> directive and its synonyms <br> </li> <li>The <a href="#ENCODE_FILE"><span style="font-family: courier new,courier,monospace; font-weight: bold;">ENCODE-FILE</span></a> directive </li> </ul> </ul> </div> <h5 style="margin-left: 40px;"><a class="mozTocH5" name="mozTocId246601"></a><a name="The_h_d_and_o_directives_"></a><big>The <span style="font-family: courier new,courier,monospace;">h#</span> <span style="font-family: courier new,courier,monospace;">d#</span> and <span style="font-family: courier new,courier,monospace;">o#</span> directives</big></h5> <div style="margin-left: 40px;">The directives <span style="font-family: courier new,courier,monospace; font-weight: bold;">h# d# </span>and <span style="font-family: courier new,courier,monospace; font-weight: bold;">o#</span> convert the token immediately following to a number, in hex, decimal or octal, respectively. <p>If the token is present, but cannot be converted to a number using the appropriate radix, i.e., if the conversion fails, the Tokenizer will issue a <a href="#A_WARNING">WARNING</a>, ignore the directive and attempt to process the token as ordinary input. If the name is not known, the "ordinary processing" will catch the error.</p> </div> <h5 style="margin-left: 40px;"><a class="mozTocH5" name="mozTocId978546"></a><big>The commands <span style="font-family: courier new,courier,monospace;">leave</span> <span style="font-family: courier new,courier,monospace;">?leave</span> or <span style="font-family: courier new,courier,monospace;">unloop</span> outside of a loop-control framework</big></h5> <div style="margin-left: 40px;">The Standard only speaks briefly about the execution consequences of this condition, and says nothing about whether a Tokenizer should permit such a sequence. This Tokenizer will report it as an <a href="#An_ERROR">Error</a> condition. </div> <h5 style="margin-left: 40px;"><a class="mozTocH5" name="mozTocId73206"></a><big>The commands <span style="font-family: courier new,courier,monospace;">[']</span> or <span style="font-family: courier new,courier,monospace;">'</span> followed by a name that is not a valid target</big></h5> <div style="margin-left: 40px;">Valid targets for the commands <span style="font-family: courier new,courier,monospace; font-weight: bold;">[']</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">'</span> are function-names that were defined during normal tokenization mode. This Tokenizer reports an <a href="#An_ERROR">Error</a> if the name following the <span style="font-family: courier new,courier,monospace; font-weight: bold;">[']</span> or <span style="font-family: courier new,courier,monospace; font-weight: bold;">'</span> is not a valid target (e.g., is the name of a macro). It will then attempt to process the name in the ordinary manner.</div> <h5 style="margin-left: 40px;"><big><a class="mozTocH5" name="mozTocId74410"></a>The Forth word <span style="font-family: courier new,courier,monospace;">to</span> followed by a name that is not a valid target</big></h5> <div style="margin-left: 40px;">The Standard specifies the Forth word <span style="font-family: courier new,courier,monospace; font-weight: bold;">to</span> as the means for setting the value of a word defined with either the <span style="font-family: courier new,courier,monospace; font-weight: bold;">value</span> or <span style="font-family: courier new,courier,monospace; font-weight: bold;">defer</span> defining-words, but says nothing about how a Tokenizer should respond to attempts to apply it to other targets. This Tokenizer reports an <a href="#An_ERROR">Error</a> if the name following the <span style="font-family: courier new,courier,monospace; font-weight: bold;">to</span> is not a valid target (e.g., is the name of a macro or a colon-definition). <p>An exception is made for a word defined as a <span style="font-family: courier new,courier,monospace; font-weight: bold;">variable</span> : Although such words are not a valid target for <span style="font-family: courier new,courier,monospace; font-weight: bold;">to</span>, many platforms' firmware will execute the sequence correctly; this Tokenizer will issue a <a href="A_WARNING">WARNING</a>.</p> </div> <h5 style="margin-left: 40px;"><big><a class="mozTocH5" name="mozTocId75614"></a><a name="Instance"></a>The word <span style="font-family: courier new,courier,monospace;">instance</span></big> </h5> <h6 style="font-weight: bold; margin-left: 80px;"><big><a name="mozTocId76818"></a>Followed by an inapplicable defining-word</big></h6> <div style="margin-left: 80px;">The Standard implies (but does not state) that, once <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> has been executed, it remains in effect until an applicable defining-word ( <span style="font-family: courier new,courier,monospace; font-weight: bold;">value</span> , <span style="font-family: courier new,courier,monospace; font-weight: bold;">variable</span> , <span style="font-family: courier new,courier,monospace; font-weight: bold;">defer</span> or <span style="font-family: courier new,courier,monospace; font-weight: bold;">buffer:</span> ) is encountered. For example, in the sequence: <p style="font-family: courier new,courier,monospace;"><span style="font-weight: bold;">instance</span> <span style="font-weight: bold;">:</span> <span>nonsense</span> <span style="font-weight: bold;">dup</span> <span style="font-weight: bold;">swap</span> <span style="font-weight: bold;">drop</span> <span style="font-weight: bold;">;</span><br> <span style="font-weight: bold;">variable</span> boombah</p> <p>the colon-definition of <span style="font-family: courier new,courier,monospace;">nonsense</span> is unaffected by the occurrence of <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> , which will, instead, be applied to the defining-word <span style="font-family: courier new,courier,monospace; font-weight: bold;">variable</span> (which defines <span style="font-family: courier new,courier,monospace;">boombah</span> ) on a later line. </p> <p>Since <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> would typically be followed immediately by the defining-word to which it is intended to apply, a sequence like the above can reasonably be presumed to be a likely error. This Tokenizer will issue a <a href="A_WARNING">WARNING</a> when an inapplicable defining-word is encountered while <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> is in effect, and another WARNING when the dangling <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> is finally applied to a valid definer. </p> </div> <h6 style="margin-left: 80px;"><big><a name="mozTocId78022"></a>Left unresolved</big></h6> <div style="margin-left: 80px;">Multiple occurrences of <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> are not cumulative; if a second <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> is encountered before the first is applied, only one occurrence of an applicable defining-word will be modified. This Tokenizer will issue a <a href="#A_WARNING">WARNING</a> when a second occurrence of <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> is encountered before the first has been applied. </div> <div style="margin-left: 80px;"> <p>The Standard says nothing about what should occur if <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> has not been applied by the time a device-node is "<span style="font-family: courier new,courier,monospace; font-weight: bold;">finish</span>"ed or a new device-node is started. In most Platforms' implementations of the FCode Interpreter, the <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> state will remain in effect. This Tokenizer will issue a WARNING the first time a device-node is changed while an <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> remains unresolved.<br> </p> </div> <h6 style="margin-left: 80px;"><a name="mozTocId79226"></a><big><a name="Instance_Not_Allowed"></a>Not Allowed in...</big></h6> <div style="margin-left: 80px;"> Although the Standard says nothing about the subject, an inclusion of <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> inside a Colon-definition would serve no purpose and is <a href="#INSTANCE_at_run_time">potentially harmful</a>; <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> should not be allowed in a Colon-definition. This Tokenizer will detect an attempt to compile <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> into a Colon-definition and report it as an <a href="#An_ERROR">Error</a> condition. <p>Also, <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> can not be allowed when <a href="#Global_Definitions">Global Scope</a> is in effect, as <a href="#INSTANCE_at_run_time">explained elsewhere</a>.<br> </p> </div> <h5 style="margin-left: 40px;"><a class="mozTocH5" name="mozTocId884280"></a><big>The command <span style="font-family: courier new,courier,monospace;">fload</span> inside a colon-definition</big></h5> <div style="margin-left: 40px;">If the command <span style="font-family: courier new,courier,monospace; font-weight: bold;">fload</span> is encountered while a colon-definition is in progress, this Tokenizer will process it immediately, and read the contents of the <span style="font-family: courier new,courier,monospace; font-weight: bold;">fload</span>ed file as a continuation of Source input. </div> <h4 style="margin-left: 40px;"><a class="mozTocH4" name="mozTocId901662"></a>Non-Standard Synonyms for Standard Functions</h4> <div style="margin-left: 40px;">This Tokenizer accepts the following non-Standard words as synonyms for the Standard words, as listed:<br> <ul> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">ENDIF</span> as a synonym for <span style="font-family: courier new,courier,monospace; font-weight: bold;">THEN</span></li> <li><span style="font-family: courier new,courier,monospace; font-weight: bold;">NAME</span> as a synonym for <span style="font-family: courier new,courier,monospace; font-weight: bold;">DEVICE-NAME</span></li> </ul> </div> <h4 style="margin-left: 40px;"><a class="mozTocH4" name="mozTocId732819"></a>Non-Standard Functions or behaviors</h4> <div style="margin-left: 40px;">This section will discuss features supported by this Tokenizer that extend capabilities regarded by the Standard as unsupportable, or that are left only vaguely specified as "implementation-dependent". It will also present a few minor items that are introduced as conveniences for the User.<br> </div> <h5 style="margin-left: 80px;"><a class="mozTocH5" name="mozTocId522750"></a><a name="Alias"></a><big>Alias</big></h5> <p style="margin-left: 80px;">In normal tokenization mode the <span style="font-family: courier new,courier,monospace; font-weight: bold;">alias</span> directive behaves as specified in the Standard, i.e., it creates a new command with the exact behavior of an existing command. Any occurrence of the new command will cause the assigned FCode of the old command to be generated, with all the implications that follow from that.</p> <p style="margin-left: 80px;">The Standard, further, states that: "In FCode source, <span style="font-family: courier new,courier,monospace; font-weight: bold;">alias</span> cannot be called from within a colon definition." However, this Tokenizer can handle that, and issues a <a href="#A_WARNING">WARNING</a> message when it does so.</p> <p style="margin-left: 80px;">The Standard does not specify the behavior of <span style="font-family: courier new,courier,monospace; font-weight: bold;">alias</span> in "Tokenizer Escape" mode. This Tokenizer will allow <span style="font-family: courier new,courier,monospace; font-weight: bold;">alias</span> commands issued in "Tokenizer Escape" mode to take effect in that mode, and, furthermore, aliases to words that are recognized in either mode may be created in either mode and will be recognized in either mode.<br> </p> <p style="margin-left: 80px;">Generally speaking, an alias definition will take on the <a href="#Scope_Directives">Scope</a> that is current at the time it is made: If Device Scope is in effect, the new name -- even if it is an alias to a word that has <a href="#Global_Definitions">Global scope</a> -- will only be accessible from the <span style="font-family: courier new,courier,monospace; font-style: italic;">current device-node</span>. An <a href="#Advisories">ADVISORY</a> message will be issued for this condition. </p> <h5 style="margin-left: 80px;"><a class="mozTocH5" name="mozTocId824541"></a><a name="String_Gathering_Features"></a> <big>String-Escape characters and other String-Gathering Features</big></h5> <div style="margin-left: 80px;">The Standard specifies, in effect, that a string is terminated by a double-quote (the <span style="font-family: courier new,courier,monospace; font-weight: bold;">"</span> character) when it is immediately followed by whitespace; that if the <span style="font-family: courier new,courier,monospace; font-weight: bold;">"</span> is followed by an open-parenthesis, hex-sequence parsing begins until a close-parenthesis is found; and that if the <span style="font-family: courier new,courier,monospace; font-weight: bold;">"</span> is followed by any other character, "the result is implementation-dependent".<br> <h6 style="margin-left: 40px;"><big><a class="mozTocH5" name="mozTocId945290"></a>Quoted String-Escape Characters</big></h6> <p style="margin-left: 40px;">Common practice -- widely enough used as to merit consideration as an undocumented de-facto standard -- has been to recognize a set of letters and to translate them into special characters when they immediately follow the <span style="font-family: courier new,courier,monospace; font-weight: bold;">"</span> .<br> </p> <p style="margin-left: 40px;">This Tokenizer translates String-Escape Quoted-pairs as follows: </p> <p style="margin-left: 60px;"> <table style="text-align: left; width: 100%;" border="0" cellpadding="1" cellspacing="4"> <tbody> <tr> <td style="vertical-align: top; text-align: left; width: 105px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">"n</span> </td> <td style="vertical-align: top;">New-Line </td> </tr> <tr> <td style="vertical-align: top; text-align: left; width: 105px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">"l</span></td> <td style="vertical-align: top;">New-Line</td> </tr> <tr> <td style="vertical-align: top; text-align: left; width: 105px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">"r</span></td> <td style="vertical-align: top;">Carriage-Return</td> </tr> <tr> <td style="vertical-align: top; text-align: left; width: 105px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">"t</span></td> <td style="vertical-align: top;">Horizontal Tab</td> </tr> <tr> <td style="vertical-align: top; text-align: left; width: 105px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">"f</span></td> <td style="vertical-align: top;">Form-Feed</td> </tr> <tr> <td style="vertical-align: top; text-align: left; width: 105px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">"b</span></td> <td style="vertical-align: top;">Backspace</td> </tr> <tr> <td style="vertical-align: top; text-align: left; width: 105px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">"!</span></td> <td style="vertical-align: top;">Bell</td> </tr> <tr> <td style="vertical-align: top; text-align: left; width: 105px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">"<span style="font-style: italic;">^</span></span><span style="font-family: arial; font-style: italic;">L</span></td> <td style="vertical-align: top;">Quote-Caret followed by a letter is translated as "Control"-<span style="font-family: arial; font-style: italic;">the-letter</span>.</td> </tr> <tr> <td style="vertical-align: top; text-align: left; width: 105px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">"</span><span style="font-family: arial; font-style: italic;">Other</span></td> <td style="vertical-align: top;">Any unrecognized character following the <span style="font-family: courier new,courier,monospace; font-weight: bold;">"</span> is taken verbatim.<br> </td> </tr> <tr> <td style="vertical-align: top;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">""</span></td> <td style="vertical-align: top;">The way to embed a double-quote into a string is to escape it with itself. (This is a special instance of the preceding rule)<br> </td> </tr> <tr> <td style="vertical-align: top; text-align: left; width: 105px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">"(</span></td> <td style="vertical-align: top;">As was mentioned above, Quote-Open-Parenthesis begins parsing a hex-sequence as per Section A.2 of the Standard under the description of the <span style="font-family: courier new,courier,monospace; font-weight: bold;">"</span> operator. Details will be discussed <a href="#Hex_Seq_Procg">below</a>.<br> </td> </tr> <tr> <td style="vertical-align: top; text-align: left; width: 105px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">"\<a name="SFeat_Str_Rem_Esc"></a></span></td> <td style="vertical-align: top;">Quote-Backslash permits insertion of remarks into the middle of a string definition; it will interrupt string parsing, causing the remainder of the line, together with any whitespace that might begin the new line, to be ignored. <p>Because this feature is not in usual practice, the User can disable it by invoking the <a href="#SF_Flag_Str_Rem_Esc"><span style="font-family: courier new,courier,monospace; font-weight: bold;">noString-remark-escape</span></a> <a href="#Special_Feature_Flags"> Special-Feature Flag</a>.</p> <p>If this feature is disabled, the Backslash following the <span style="font-family: courier new,courier,monospace; font-weight: bold;">"</span> will be taken verbatim; the Backslash, the text following it on the remainder of the line, the new-line and the whitespace on the next line -- all of which would otherwise have been ignored -- will be included in the string parsing and incorporated into the result. </p> </td> </tr> </tbody> </table> </p> </div> <div style="margin-left: 120px;"> <h6><big><a class="mozTocH5" name="mozTocId758170"></a>Embedded New-Lines</big></h6> <p>The Standard makes no mention about what to do when a string reaches a new-line before its termination. This Tokenizer continues parsing and includes the new-line, together with any whitespace that might begin the new line, in the result.<br> </p> <h6><big><a class="mozTocH5" name="mozTocId42456"></a><a name="Hex_Seq_Procg"></a>Hex-Sequence Processing</big></h6> The Standard mentions parsing hexadecimal characters in pairs in the substring between <span style="font-family: courier new,courier,monospace; font-weight: bold;">"(</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">)</span> but makes no mention of what to do when a single hexadecimal character appears between nonhexadecimal characters. The usual practice is to treat it as representing the low-order digit of a single byte, and this Tokenizer follows that convention.<br> <p><a name="SFeat_Hex_Rem_Esc"></a>This Tokenizer also supports an option -- not in usual practice, hence listed separately here -- that permits insertion of remarks in the middle of a hex-sequence in a string. The occurrence of a single <span style="font-family: courier new,courier,monospace; font-weight: bold;">\</span> (backslash) character will interrupt hex-sequence parsing, causing the remainder of the line, together with any whitespace that might begin the next line, to be ignored. The User can disable this feature by invoking the <a href="#SF_Flag_Hex_Rem_Esc"><span style="font-family: courier new,courier,monospace; font-weight: bold;">noHex-remark-escape</span></a> <a href="#Special_Feature_Flags"> Special-Feature Flag</a>.<br> </p> <p>If the Hex-Remark-Escape feature is disabled, the Backslash will be treated as an ordinary nonhexadecimal character, and Hex-Sequence parsing will proceed. Any hexadecimal characters on the remainder of the line -- which would otherwise have been ignored -- will be recognized and incorporated into the result. </p> <h6><big><a class="mozTocH5" name="mozTocId150131"></a><a name="C-Style_String-Escape_Characters"></a><big>C</big>-Style String-Escape Characters</big></h6> In addition to the Quoted String-Escape sequences, this Tokenizer recognizes a small subset of the Backslash-based String-Escape pairs that are used in <big><b>C</b></big> and translates them similarly. <p>Specifically, <span style="font-family: courier new,courier,monospace; font-weight: bold;">\n</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">\t</span> are translated into New-Line and Horizontal Tab respectively.</p> <p><a name="SFeat_BS_xx"></a>If the Backslash is followed by other characters, the Tokenizer will attempt to read them as a digit-string, using the current base, and create a numeric byte. The numeric sequence ends with the first non-numeric character (which is treated as a delimiter and consumed, unless it's a double-quote, in which case it's allowed to terminate the string or apply whatever action is triggered by the character following it). If the value represented by the numeric sequence exceeds the size of a byte, its low-order byte will be used and a <a href="#A_WARNING">WARNING</a> will be issued. </p> <p>If the first character after the backslash was non-numeric, the character will be used literally (and a WARNING will be issued). As in <big><b>C</b></big>, the backslash can be used to escape itself. </p> </div> <p style="margin-left: 120px;">The User can disable this feature by invoking the <a href="#SF_Flag_C_Str_Esc"><span style="font-family: courier new,courier,monospace; font-weight: bold;">noC-Style-string-escape</span></a> <a href="#Special_Feature_Flags">Special-Feature Flag</a>. </p> <h5 style="margin-left: 80px;"><a class="mozTocH5" name="mozTocId40998"></a><big><a name="SFeat_AB_Q"></a>The <big><span style="font-family: courier new,courier,monospace;">ABORT"</span></big> (Abort-Quote) command<br> </big></h5> <div style="margin-left: 80px;">The Standard is not very clear about the use of this FORTH command, and does not assign it an FCode. Nonetheless, it has historically been treated as a macro, and this Tokenizer will support that treatment.<br> <p><a name="SFeat_Sun_AB_Q"></a>To complicate matters, there are two distinct styles in which this macro is used in FCode drivers, "Apple" style and "Sun" style:<br> </p> <p>In Sun Style, the sequence, in the Source, would look like this:<br> </p> <p style="margin-left: 40px;"><span style="font-family: courier new,courier,monospace;"><span style="font-style: italic;"><Condition></span> <span style="font-weight: bold;">ABORT"</span> <span style="font-style: italic;">Message text</span><span style="font-weight: bold;">"</span></span></p> <p>Semantically, it would mean that if the <span style="font-family: courier new,courier,monospace; font-style: italic;"><Condition></span> is true, the <span style="font-family: courier new,courier,monospace; font-style: italic;">Message text</span> would be printed and a <span style="font-family: courier new,courier,monospace; font-weight: bold;">-2 THROW</span> would be performed; conversely, if the <span style="font-family: courier new,courier,monospace; font-style: italic;"><Condition></span> is false, the <span style="font-family: courier new,courier,monospace; font-style: italic;">Message text</span> would be bypassed and execution would continue with the next token after. </p> <p>The sequence could be translated into FCode as a macro like this:</p> <div style="margin-left: 40px;"><span style="font-family: courier new,courier,monospace;"><span style="font-style: italic;"><Condition></span> <span style="font-weight: bold;">IF</span> <span style="font-weight: bold;">"</span> <span style="font-style: italic;">Message text</span><span style="font-weight: bold;">" TYPE</span> <span style="font-weight: bold;">-2 THROW</span> <span style="font-weight: bold;">THEN</span></span><br> </div> <p>In Apple Style, the Source supplies the surrounding <span style="font-family: courier new,courier,monospace; font-weight: bold;">IF</span> ... <span style="font-family: courier new,courier,monospace; font-weight: bold;">THEN</span> . The action of the <span style="font-family: courier new,courier,monospace; font-weight: bold;">ABORT"</span> command is to leave the <span style="font-family: courier new,courier,monospace; font-style: italic;">Message text</span> on the stack and perform the <span style="font-family: courier new,courier,monospace; font-weight: bold;">-2 THROW</span> unconditionally, with the expectation that the system <span style="font-family: courier new,courier,monospace; font-weight: bold;">CATCH</span> will print the string it finds on the stack. <br> </p> <p>The Source sequence would look like this:<br> </p> <p style="margin-left: 40px;"><span style="font-family: courier new,courier,monospace;"><span style="font-style: italic;"><Condition></span> <span style="font-weight: bold;">IF</span> <span style="font-weight: bold;">ABORT"</span> <span style="font-style: italic;">Message text</span><span style="font-weight: bold;">" </span><span style="font-weight: bold;">THEN</span></span><br> </p> <p>The <span style="font-family: courier new,courier,monospace; font-weight: bold;">ABORT"</span> ... <span style="font-family: courier new,courier,monospace; font-weight: bold;">"</span> portion of the sequence would be translated into FCode as a macro like this:</p> <div style="margin-left: 40px;"><span style="font-family: courier new,courier,monospace;"><span style="font-weight: bold;">"</span> <span style="font-style: italic;">Message text</span><span style="font-weight: bold;">"</span> <span style="font-weight: bold;">-2 THROW </span></span><br> </div> <p>Because the <span style="font-family: courier new,courier,monospace; font-weight: bold;">ABORT"</span> command is not specified in the Standard, the User can disable it by invoking the <a href="#SF_Flag_AB_Q"><span style="font-family: courier new,courier,monospace; font-weight: bold;">noABORT-Quote</span></a> <a href="#Special_Feature_Flags">Special-Feature Flag</a>. </p> <p>The User who chooses to enable this feature, can, further, select to disable "Sun" style in favor of "Apple" style by invoking the <a href="#SF_Flag_Sun_AB_Q"><span style="font-family: courier new,courier,monospace; font-weight: bold;">noSun-ABORT-Quote</span></a> <a href="#Special_Feature_Flags">Special-Feature Flag</a>.<br> </p> <p><a name="Abort_Quote_Abort"></a>And to complicate matters even further, some Legacy applications prefer to use the <span style="font-family: courier new,courier,monospace; font-weight: bold;">ABORT</span> command (note there's no quote) in place of the <span style="font-family: courier new,courier,monospace; font-weight: bold;">-2 THROW</span> sequence. Although the <span style="font-family: courier new,courier,monospace; font-weight: bold;">ABORT</span> command is not recommended, it <span style="font-style: italic;">is</span> a legitimate FCode function, and this Tokenizer supports a <a href="#Special_Feature_Flags">Special-Feature Flag</a>, called <a href="#SF_Flag_AB_Q_Throw">Abort-Quote-Throw</a>, which controls whether an <span style="font-family: courier new,courier,monospace; font-weight: bold;">ABORT"</span> (Abort-Quote) phrase will be tokenized with the <span style="font-family: courier new,courier,monospace; font-weight: bold;">-2 THROW</span> sequence or with the <span style="font-family: courier new,courier,monospace; font-weight: bold;">ABORT</span> function. The User who chooses to have <span style="font-family: courier new,courier,monospace; font-weight: bold;">ABORT"</span> (Abort-Quote) phrases tokenized with the <span style="font-family: courier new,courier,monospace; font-weight: bold;">ABORT</span> function can do so by invoking <a href="#SF_Flag_AB_Q_Throw">noAbort-Quote-Throw</a> </p> </div> <h5 style="margin-left: 80px;"><a name="mozTocId526780"></a><big><a name="Char_Seq_To_Num"></a>Conveniently Convert Short Character-Sequence to Number</big><br> </h5> <p style="margin-left: 80px;">Occasionally, a User needs to create a numeric constant whose value corresponds to a short sequence of characters. For instance, <span style="font-family: courier new,courier,monospace; font-weight: bold;">PCIR</span> will get coded as <span style="font-family: courier new,courier,monospace; font-weight: bold;">h# 50434952</span>. This tokenizer supports a convenient directive called <span style="font-family: courier new,courier,monospace; font-weight: bold;">a#</span> , syntactically similar to <a href="#The_h_d_and_o_directives_"><span style="font-family: courier new,courier,monospace; font-weight: bold;">h# d# </span>and <span style="font-family: courier new,courier,monospace; font-weight: bold;">o#</span></a> , which makes the conversion directly. The above example can be written: <span style="font-family: courier new,courier,monospace; font-weight: bold;">a# PCIR</span> , sparing the programmer -- and the maintainer -- from needing to translate ASCII on the fly.<br> </p> <p style="margin-left: 80px;">The <span style="font-family: courier new,courier,monospace; font-weight: bold;">a#</span> operator expects its target argument <a href="#Expected_on_same_line">on the same line</a>.<br> </p> <p style="margin-left: 80px;">If the target-sequence contains more than four characters, the last four will become the number; if the target-sequence contains fewer than four characters, they will fill the low-order part of the number. (I.e., the operation of <span style="font-family: courier new,courier,monospace; font-weight: bold;">a#</span> is right-justified.) Thus:<br> </p> <div style="margin-left: 160px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">a# CPU</span> is equivalent to <span style="font-family: courier new,courier,monospace; font-weight: bold;">h# 00435055</span> </div> <div style="margin-left: 120px;"> and </div> <div style="margin-left: 160px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">a# LotsOfStuff</span> is equivalent to <span style="font-family: courier new,courier,monospace; font-weight: bold;">a# tuff</span> or <span style="font-family: courier new,courier,monospace; font-weight: bold;">h# 74756666</span></div> <p style="margin-left: 80px;">Also, the conversion is case-sensitive: <span style="font-family: courier new,courier,monospace; font-weight: bold;">a# cpu</span> is equivalent to <span style="font-family: courier new,courier,monospace; font-weight: bold;">h# 00637075</span></p> <h6 style="margin-left: 120px;"><a class="mozTocH5" name="mozTocId53626"></a><big><a name="Char_to_Num_Left_Justified"></a>Left-Justified</big></h6> <div style="margin-left: 120px;">To accommodate situations that call for the characters to occupy the high-order part of the number, this Tokenizer supports an "Ascii-Left" conversion directive called <span style="font-family: courier new,courier,monospace; font-weight: bold;">al#</span> , which is equivalent to <span style="font-family: courier new,courier,monospace; font-weight: bold;">a#</span> in all respects except when the target-sequence contains fewer than four characters: <span style="font-family: courier new,courier,monospace; font-weight: bold;">al# CPU</span> is equivalent to <span style="font-family: courier new,courier,monospace; font-weight: bold;">h# 43505500</span></div> <h5 style="margin-left: 80px;"><a class="mozTocH5" name="mozTocId54171"></a><a name="F_Eff-Bracket-Tick-Bracket"></a><big>F['] ("Eff-Bracket-Tick-Bracket")</big></h5> <p style="margin-left: 80px;">Syntactically similar to the Standard <span style="font-family: courier new,courier,monospace; font-weight: bold;">[']</span> ("Bracket-Tick-Bracket"). Valid targets for <span style="font-family: courier new,courier,monospace; font-weight: bold;">F[']</span> are the same as for <a href="#mozTocId73206"><span style="font-family: courier new,courier,monospace; font-weight: bold;">[']</span> or <span style="font-family: courier new,courier,monospace; font-weight: bold;">'</span></a> . Attempts to apply <span style="font-family: courier new,courier,monospace; font-weight: bold;">F[']</span> to an invalid target will be handled similarly.<br> </p> <p style="margin-left: 80px;">This directive acquires the given word's FCode-Token number, which is then used according to whether the directive is invoked during "Normal Tokenization" or "Tokenizer-Escape" mode:</p> <h6 style="margin-left: 120px;"><big><big><a name="mozTocId54716"></a><a name="F_B-T-B_Normal"></a>F['] in "Normal Tokenization" Mode:</big></big></h6> <p style="margin-left: 120px;">The given word's FCode-Token number is tokenized as a literal, which can be used, for instance, as the argument to a <span style="font-family: courier new,courier,monospace; font-weight: bold;">get-token</span> or <span style="font-family: courier new,courier,monospace; font-weight: bold;">set-token</span> command.<br> </p> <div style="margin-left: 120px;">For example, the sequence:<big> </big><br> </div> <div style="margin-left: 200px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">F['] rl@ get-token</span><span style="font-family: helvetica,arial,sans-serif;"></span> </div> <div style="margin-left: 160px;">is equivalent to:<big> </big><br> </div> <div style="margin-left: 200px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;"> h# 234 get-token</span><br> </div> <h6 style="margin-left: 120px;"><big><big><a name="mozTocId55261"></a><a name="F_B-T-B_TkzEsc"></a>F['] in "Tokenizer-Escape" Mode:</big></big></h6> <p style="margin-left: 120px;">This function is the one <a href="#Tkz_Esc_Scope">exception to the general rule</a> about the <a href="#Scope_Directives">scope</a> of words recognized in "Tokenizer-Escape" mode; it will recognize function-names that were defined during normal tokenization mode and that were <a href="#current_device-node">current at the time</a> "Tokenizer-Escape" mode was entered.<br> </p> <p style="margin-left: 120px;">The given word's FCode-Token number is pushed onto the data-stack, from whence it can be used, for instance, as the numeric argument to a <a href="#Tkz_Esc_Const"><span style="font-family: courier new; font-weight: bold;">constant</span></a> definition.<br> </p> <h5 style="margin-left: 80px;"><a name="mozTocId887752"></a><big><a name="Shell_Env_Vbles_in_File_Names"></a>Shell-Environment Variables in File-Names</big></h5> <p style="margin-left: 80px;">The filename that follows the <span style="font-family: courier new,courier,monospace; font-weight: bold;">fload</span> command or the <a href="#ENCODE_FILE"><span style="font-family: courier new,courier,monospace; font-weight: bold;">encode-file</span></a> directive may be an absolute path, a path relative to the Current Working Directory, or a path relative to one of the directories in the <a href="#Include_List">Include-List</a>. It may also contain Shell Environment Variables and related expressions recognized by the Host Operating System environment in which the Tokenizer is running. These will all be expanded before loading the file. An illustration may be seen in <a href="#Example_4">Example #4</a>. </p> <p style="margin-left: 80px;">An <a href="#Advisories">ADVISORY</a> message showing the expanded value will be printed if the <a style="font-style: italic; font-weight: bold;" href="#verbose_option">verbose</a> <a href="#Command-Line_options_">option</a> has been selected or in the event of a failure to read the file.<br> </p> <h4 style="margin-left: 40px;"><a class="mozTocH4" name="mozTocId505746"></a>Featured behaviors, supported by this Tokenizer, that are not mentioned in the Standard</h4> <h5 style="margin-left: 80px;"><a name="mozTocId530910"></a><big><a name="Macros"></a>User-Defined Macros</big></h5> <div style="margin-left: 80px;">The Standard mentions built-in tokenizer macros (such as <span style="font-family: courier new,courier,monospace;">3drop</span> for example) but makes no provision for the User to define any additional macros. <p>This Tokenizer supports a directive that allows the User to define additional macros. Its syntax is:</p> <p style="margin-left: 40px;"> <span style="font-family: courier new,courier,monospace; font-weight: bold;">[macro]</span> <span style="font-family: courier new,courier,monospace;"><<span style="font-style: italic;">macroname</span>> <span style="font-style: italic;">cmnd1 cmnd2 cmnd3 ... cmndN</span></span></p> <p>The entire body of the macro definition must be contained on a single line. The linefeed at the end of the line will be included as part of the macro definition.<br> </p> <p>In this Tokenizer, macros are implemented as simple string substitutions, interpreted at the time they are invoked. If a component of the macro should change its meaning -- i.e., be redefined -- then, on subsequent invocations of the macro, the new meaning will take effect. (Note that this is different from an <a href="#Alias">alias</a>). It is also (eminently) possible to define a macro that uses a name that has not been defined at the time the macro is defined, to define that name later, and to invoke the macro after the name has been defined. This is legitimate and will work.<br> </p> <p>For the same reason, macros may be nested; i.e., one macro may be defined in such a way as to invoke another. However, if a macro -- or a series of nested macros -- were to invoke a macro that is already running, that will be detected and reported as an <a href="#An_ERROR">Error</a> condition. For a simple example, a User who needed to identify all occurrences of the word <span style="font-family: courier new,courier,monospace; font-weight: bold;">2drop</span> might attempt to write:</p> <div style="margin-left: 40px; font-family: courier new,courier,monospace;"> <span style="font-weight: bold;">overload</span> <span style="font-weight: bold;">[macro]</span> 2drop <span style="font-weight: bold;">message"</span> 2DROP called here<span style="font-weight: bold;">"</span> <span style="font-weight: bold;">2drop</span> </div> in the expectation that the second <span style="font-family: courier new,courier,monospace; font-weight: bold;">2drop</span> would be interpreted as the generic one, which outputs the corresponding token. <p>However, because the macro definition is not "compiled" in the same way as a colon-definition, but is, instead, interpreted at run-time, the <span style="font-family: courier new,courier,monospace; font-weight: bold;">2drop</span> that would be executed would, in fact, be the macro itself, leading to an infinite loop of messages (if the condition were not detected...). In order to protect against this condition, the User should, instead, do something like this:</p> <div style="margin-left: 40px; font-family: courier new,courier,monospace;">\ Keep a "generic" 2DROP handy.<br> <span style="font-weight: bold;">alias</span> generic-2drop 2drop<br> <span style="font-weight: bold;">overload</span> <span style="font-weight: bold;">[macro]</span> 2drop <span style="font-weight: bold;">message"</span> 2DROP called here<span style="font-weight: bold;">" </span>generic-2drop </div> <p> This has the added advantage that, when the passage in which the notification is needed comes to an end, the User can restore <span style="font-family: courier new,courier,monospace; font-weight: bold;">2drop</span> to its Standard behavior with:<br> </p> <div style="margin-left: 40px; font-family: courier new,courier,monospace;"><span style="font-weight: bold;">overload</span> <span style="font-weight: bold;">alias</span> 2drop generic-2drop</div> <p>A User-Defined Macro takes on the <a href="#Scope_Directives">Scope</a> that is current at the time it is created. An illustration may be seen in <a href="#Example_4">Example #4</a>. </p> </div> <h5 style="margin-left: 80px;"><a class="mozTocH5" name="mozTocId539069"></a><big><a name="Multiple_device_nodes"></a>Multiple device-nodes</big></h5> <div style="margin-left: 80px;">The typical use of a tokenizer is to write a driver for a single-node device. For such an application, the commands <span style="font-family: courier new,courier,monospace; font-weight: bold;">new-device</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">finish-device</span> are not required. However, many newer devices consist of complexes of subordinate and peer devices within a single assembly; some additional caution is required when developing drivers for such configurations.<br> <p><a name="INSTANCE_at_run_time"></a>In particular, an attempt within one device-node to access directly a method defined in another device-node must be flagged as an error. Consider what would happen at run-time if it were allowed: the called method would be expecting the instance-pointer to be pointing to the instance data of the device-node in which that method was defined, but it would, instead, be pointing to the instance data of the device-node that made the call. This is an invitation to havoc that would be -- to put it politely -- somewhat difficult to trace.<br> </p> <p>The correct way to invoke a method across device-node boundaries is via <span style="font-family: courier new,courier,monospace; font-weight: bold;">$call-parent</span> or <span style="font-family: courier new,courier,monospace; font-weight: bold;">$call-method</span> or the like.<br> </p> <p><a name="device-node_vocabularies"></a>In order to detect such errors early on, this Tokenizer keeps track of separate but linked "vocabularies" associated with device-nodes. When the command <span style="font-family: courier new,courier,monospace; font-weight: bold;">new-device</span> is encountered in interpretation mode, a new device-node vocabulary is opened and new definitions are entered into it. Definition-names created in the preceding device-node -- presumably the parent of the newly started device -- are suspended from accessiblity. <br> </p> <p>Correspondingly, when the <span style="font-family: courier new,courier,monospace; font-weight: bold;">finish-device</span> command is encountered in interpretation mode, the "vocabulary" of the device being ended is emptied ("forgotten" in classic Forth parlance) and the "vocabulary" of the parent-device is resumed.<br> </p> <p><a name="current_device-node"></a>The device-node vocabulary to which definitions are being entered at any given time, and from which definitions are accessible, may be referred to as the <span style="font-family: courier new,courier,monospace; font-style: italic;">current device-node</span> for purposes of discussion.<br> </p> <p>Note that the Tokenizer does not switch vocabularies when the <span style="font-family: courier new,courier,monospace; font-weight: bold;">new-device</span> or <span style="font-family: courier new,courier,monospace; font-weight: bold;">finish-device</span> commands are encountered in compilation mode (i.e., when they are being compiled-in to a method); they are treated as ordinary tokens, since the shift to a new device-node will not occur until run-time. </p> <p>The commands <span style="font-family: courier new,courier,monospace; font-weight: bold;">new-device</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">finish-device</span> must remain in balance. If a <span style="font-family: courier new,courier,monospace; font-weight: bold;">finish-device</span> is encountered without a prior corresponding <span style="font-family: courier new,courier,monospace; font-weight: bold;">new-device</span>, or if the end of FCode (or a <a href="#Resetting_Symbols_Defined_in_Either_Mode"><span style="font-family: courier new,courier,monospace; font-weight: bold;">Reset-Symbols</span></a> directive issued in "normal" mode) is reached and not all occurrences of <span style="font-family: courier new,courier,monospace; font-weight: bold;">new-device</span> are balanced by a call to <span style="font-family: courier new,courier,monospace; font-weight: bold;">finish-device</span>, it will be reported as an <a href="#An_ERROR">Error</a> condition. </p> <p>Definitions made in "Tokenizer-Escape" mode, however, are independent of device-node vocabularies and remain accessible until they are explicitly reset by a <a href="#Resetting_Symbols_Defined_in_Either_Mode"><span style="font-family: courier new,courier,monospace; font-weight: bold;">Reset-Symbols</span></a> directive issued in "Tokenizer-Escape" mode.<br> </p> </div> <h6 style="margin-left: 120px;"><a name="mozTocId540605"></a><big><big><a name="Global_Definitions"></a>Global Definitions</big></big></h6> <div style="margin-left: 120px;">Occasionally, the User might need to create definitions of methods that are intended to be directly accessible to all the device-nodes in a driver, even though they reside in one device node. Such definitions are, effectively, added to the "core" vocabulary, and are Global in scope. <a href="#Scope_Directives">Directives</a> to control the creation of Global Definitions are supported by this Tokenizer.</div> <h5 style="margin-left: 80px;"><a class="mozTocH5" name="mozTocId354426"></a><big><a name="Multiple_FCode-block_Images"></a>Multiple FCode-block Images</big></h5> <div style="margin-left: 80px;">In addition to supporting complexes of subordinate and peer devices within a single assembly, this Tokenizer supports configurations in which subordinate devices' drivers are kept in separate but related FCode blocks. This is accomplished simply by invoking multiple bodies of code bracketed by <span style="font-family: courier new,courier,monospace; font-weight: bold;">fcode-version<span style="font-style: italic;"><</span></span><span style="font-family: courier new,courier,monospace; font-style: italic;">n</span><span style="font-family: courier new,courier,monospace; font-weight: bold; font-style: italic;">></span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">fcode-end</span> (or one of its synonyms).<br> <p>When the <span style="font-family: courier new,courier,monospace; font-weight: bold;">fcode-end</span> (or equivalent) that ends one body of code is processed, and before the <span style="font-family: courier new,courier,monospace; font-weight: bold;">fcode-version<span style="font-style: italic;"><</span></span><span style="font-family: courier new,courier,monospace; font-style: italic;">n</span><span style="font-family: courier new,courier,monospace; font-weight: bold; font-style: italic;">></span> that begins the next, the definitions that had been created are forgotten, but assignment of FCode-token numbers will continue in sequence. Likewise, definitions made in "Tokenizer-Escape" mode will persist.<br> </p> <p>The User who desires to reset one or the other of these, or both, can do so by issuing the directives:<br> </p> <div style="margin-left: 40px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">FCode-Reset<br> </span> <div style="margin-left: 40px;">or<br> </div> </div> <div style="margin-left: 40px;"><span style="font-family: courier new,courier,monospace; font-weight: bold;">Reset-Symbols</span><br> </div> </div> <div style="margin-left: 40px;"> <div style="margin-left: 40px;"><br> respectively, in "Tokenizer-Escape" mode. This is illustrated in <a href="#Example_3">Example #3</a>.<br> </div> </div> <h5 style="margin-left: 80px;"><a class="mozTocH5" name="mozTocId232809"></a><big><a name="Multiple_PCI_Image"></a>Multiple PCI-Image</big></h5> <div style="margin-left: 80px;">The PCI Standard allows for a chain of PCI Images to be bundled together in a single binary (as indicated by the <a href="#Last_Image_Indicator_bit">"Last Image" bit</a>). This Tokenizer supports such configurations by correctly processing Source that contains multiple occurrences of blocks of code bracketed by <span style="font-family: courier new,courier,monospace; color: rgb(68, 34, 0); font-weight: bold;">pci-header</span> ... <span style="font-family: courier new,courier,monospace; color: rgb(68, 34, 0); font-weight: bold;">pci-header-end</span> directives. An illustration can be seen in <a href="#Example_1">Example #1</a>, below.<br> </div> <h2><a class="mozTocH2" name="mozTocId194505"></a><a name="Examples:"></a>Examples:</h2> <h3><a class="mozTocH3" name="mozTocId544211"></a><a name="Example_1"></a>Example #1:</h3> In the first example, the "Inner Body" file has some sections that compile different code, depending on the value of a named-constant switch. The "Outer Shell " file controls the <span style="font-family: courier new,courier,monospace; font-weight: bold;">fload</span>ing of the "Inner Body": It reminds the User to specify the setting of the switch, then produces an image with two PCI-Images, based on opposite settings of the switch. Note that the use of <span style="font-family: courier new,courier,monospace; font-weight: bold; color: rgb(68, 34, 0);">Reset-Symbols</span> in "Tokenizer-Escape" mode before the redefinition of <span style="font-family: courier new,courier,monospace; color: rgb(68, 34, 0);">function-switch</span>, to avoid a "Duplicate definition" condition, may be omitted if the User is willing to tolerate the warning. <h5><a class="mozTocH5" name="mozTocId563670"></a>File: InnerBody.fth</h5> <span style="font-family: courier new,courier,monospace; color: rgb(68, 34, 0);"><span style="font-weight: bold;">fcode-version2</span><br> <span style="font-style: italic;">... Common code <obligatory sneeze> ...</span><br> <span style="font-weight: bold;">F[</span> function-switch <span style="font-weight: bold;">F]</span> <span style="font-weight: bold;">[if]</span><br> <span style="font-style: italic;">True-conditional code</span><br> <span style="font-weight: bold;">[message]</span> The true path was wisely chosen<br> <span style="font-weight: bold;">[else]</span><br> <span style="font-style: italic;">False-conditional code</span><br> <span style="font-weight: bold;">[message]</span> You have foolishly chosen the false path.<br> <span style="font-weight: bold;">[then]</span><br> <span style="font-style: italic;">... More common code <now cough>.</span><br> <span style="font-weight: bold;">end0</span></span><br> <h5><a class="mozTocH5" name="mozTocId570875"></a>File: OuterShell.fth</h5> <span style="font-family: courier new,courier,monospace; color: rgb(68, 34, 0);"><span style="font-weight: bold;">[ifndef]</span> first-path<br> <span style="font-weight: bold;">F[</span><br> <span style="font-weight: bold;">."</span> Add a command-line switch: -d ""first-path=<true|false>"" "n"\<br> <span style="font-weight: bold;"> </span> "tthen run this again.<span style="font-weight: bold;">"</span><br> <span style="font-weight: bold;">F]</span><br> <span style="font-weight: bold;">[else]</span><br> <span style="font-weight: bold;">F[</span><br> <span style="font-weight: bold;">[defined]</span> first-path <span style="font-weight: bold;">constant</span> function-switch<br> <div style="margin-left: 40px;"><span style="font-style: italic;">vendor-id</span> <span style="font-style: italic;">device1-id</span> <span style="font-style: italic;">class-code1</span> <span style="font-weight: bold;">pci-header</span><br> <span style="font-weight: bold;">F]</span><br> <span style="font-weight: bold;">not-last-image</span><br> <span style="font-weight: bold;">fload</span> InnerBody.fth<br> <span style="font-weight: bold;">pci-header-end</span><br> <br> </div> <span style="font-weight: bold;">F[</span> <span style="font-weight: bold;">reset-symbols</span><br> <span style="font-weight: bold;">[defined]</span> first-path <span style="font-weight: bold;">0=</span> <span style="font-weight: bold;">constant</span> function-switch<br> <div style="margin-left: 40px;"><span style="font-style: italic;">vendor-id</span> <span style="font-style: italic;">device2-id</span> <span style="font-style: italic;">class-code2</span> <span style="font-weight: bold;">pci-header</span><br> <span style="font-weight: bold;">F]</span><br> <span style="font-weight: bold;">last-image</span><br> <span style="font-weight: bold;">fload</span> InnerBody.fth<br> <span style="font-weight: bold;">pci-header-end</span><br> </div> <span style="font-weight: bold;">[then]</span></span><br> <h5><a class="mozTocH5" name="mozTocId953372"></a>Command-Line invocation:</h5> <span style="font-family: courier new,courier,monospace; color: rgb(68, 34, 0); font-weight: bold;">toke -v -d "first-path=true" OuterShell.fth</span><br> <br> <h3><a class="mozTocH3" name="mozTocId80432"></a><a name="Example_2"></a>Example #2:<br> </h3> <p>The second example illustrates the use of <a href="#Special_Feature_Flags">Special-Feature Flags</a> to select or de-select specific non-standard features.<br> </p> <p>The User is developing code that will run across all platforms, and therefore must must be neutral with regard to "Sun"- or "Apple"- -style usage of <span style="font-family: courier new,courier,monospace; font-weight: bold;">ABORT"</span> ; this can be best achieved by disallowing the use of <span style="font-family: courier new,courier,monospace; font-weight: bold;">ABORT"</span> altogether. </p> <p>There is no concern, however, about compatibility of the Source with other Tokenizers, so the User need not forgo the conveniences of Local Values and String-remark-escapes. </p> <p>Furthermore, the Source contains many passages taken from IBM Legacy sources, and the User does not wish to see a WARNING message when the Legacy Locals Separator is used. </p> <p>The command-line for these conditions would include the following:</p> <span style="font-family: courier new,courier,monospace; color: rgb(68, 34, 0); font-weight: bold;">toke -f NOabort-quote -f local-values -f NOlv-legacy-warning</span> <p>Alternatively, these flags may be set from <a href="#Changing_C-L_Flags_from_Source">within the Source code</a> thus: </p> <div style="margin-left: 40px; color: rgb(68, 34, 0); font-family: courier new,courier,monospace; font-weight: bold;">[flag] NOabort-quote<br> [flag] local-values<br> [flag] NOlv-legacy-warning </div> <p>Note that the invocation of <span style="font-family: courier new,courier,monospace; color: rgb(68, 34, 0);">-f local-values</span> is necessary, as its default state is to be disabled. Also, because <span style="font-family: courier new,courier,monospace; color: rgb(68, 34, 0);">-f NOabort-quote</span> is invoked, the setting of the <span style="font-family: courier new,courier,monospace; font-weight: bold;">Sun-ABORT-Quote</span> flag is irrelevant.<br> </p> <h3><a class="mozTocH3" name="mozTocId455242"></a><a name="Example_3"></a>Example #3:</h3> <p>The third example illustrates two situations where two or three <a href="#Multiple_FCode-block_Images">FCode blocks</a> are incorporated into a single PCI Image.<br> </p> <p>In the first situation, the "Outer" block will <span style="font-family: courier new,courier,monospace; font-weight: bold;">byte-load</span> the code of the "Inner" block before the "Outer" block has been completely interpreted. It is therefore important to avoid collisions in FCode-token numeric assignments.<br> </p> <div style="color: rgb(68, 34, 0); font-family: courier new,courier,monospace; margin-left: 40px;"> <span style="font-weight: bold;">F[</span><br> <div style="margin-left: 40px;">h# 5afe <span style="font-weight: bold;">set-rev-level</span> <br> h# beef \ Vendor<br> h# c0de \ Device ID<br> h# 90210 \ Class Code (A "classy" ZIP Code... ;-)<br> </div> <span style="font-weight: bold;">F]</span> <span style="font-weight: bold;">pci-header</span><br> <br> <span style="font-weight: bold;">fcode-version2</span><br> <br> <span style="font-weight: bold;">fload</span> outer-block.fth<span><br> </span><br> <span style="font-weight: bold;">fcode-end<br> <br> </span><span style="font-family: helvetica,arial,sans-serif;">\ At this point, the last definition's assigned FCode number is approximately 0Xac0</span><br> <br> <span style="font-weight: bold;">fcode-version2</span><br> <br> <span style="font-family: helvetica,arial,sans-serif;">\ The next definitions' assigned FCode numbers continue from 0Xac1</span><br> <br> <span style="font-weight: bold;">fload</span> inner-block.fth<span style="font-weight: bold;"><br> </span><br> <span style="font-weight: bold;">fcode-end</span><br> <br> <span style="font-weight: bold;">pci-header-end</span><br> <br> </div> <p>In the second situation, the "Outer" block will have been completely interpreted before it begins to <span style="font-family: courier new,courier,monospace; font-weight: bold;">byte-load</span> the code of the two "Inner" blocks. It can safely discard the token-table of the interpreter, and allow its assigned FCode-token numbers to be re-cycled. Furthermore, the large number of definitions presents a real risk that the full range of usable FCode-token numbers will be exhausted. For these reasons, the User finds it necessary to reset the FCode-token numeric assignments to their initial state before tokenizing the two "Inner" blocks. <br> </p> <div style="margin-left: 40px; color: rgb(68, 34, 0); font-family: courier new,courier,monospace;"> <span style="font-weight: bold;">F[</span><br> <div style="margin-left: 40px;"> h# face <span style="font-weight: bold;">set-rev-level</span><br> h# cafe \ Vendor<br> h# d00d \ Device ID<br> h# 95014 \ Another Class(y ZIP) Code</div> <span style="font-weight: bold;">F]</span> <span style="font-weight: bold;">pci-header</span><br> <br> <span style="font-weight: bold;">fcode-version2</span><br> <br> <span style="font-weight: bold;">fload</span> outer-block.fth<br> <br> <span style="font-weight: bold;">fcode-end</span><br> <br> <span style="font-family: helvetica,arial,sans-serif;">\ At this point, the last definition's assigned FCode number is approximately 0Xae0</span><br> <br> <span style="font-weight: bold;">fcode-version2<br> <br> </span><span style="font-family: helvetica,arial,sans-serif;">\ Reset the assigned FCode numbers for the first "inner" block<br> </span><br> <span style="font-family: courier new,courier,monospace; font-weight: bold;">FCode-Reset</span><span style="font-weight: bold;"><br> </span> <br> <span style="font-weight: bold;">fload</span> inner-block_01.fth<br> <br> <span style="font-weight: bold;">fcode-end</span><br> <br> \ Load the second "inner" block.<br> <br> <span style="font-weight: bold;">fcode-version2</span><br> <br> <span style="font-family: helvetica,arial,sans-serif;">\ Reset the assigned FCode numbers for the second "inner" block</span><br> <br> <span style="font-family: courier new,courier,monospace; font-weight: bold;">FCode-Reset</span><br> <br> <span style="font-weight: bold;">fload</span> inner-block_02.fth<br> <br> <span style="font-weight: bold;">fcode-end</span><br> <br> <span style="font-weight: bold;">pci-header-end</span> </div> <br> <h3><a class="mozTocH3" name="mozTocId861304"></a><a name="Example_4"></a>Example #4</h3> <p>This example serves to illustrate the use of the directives that control the <a href="#Scope_Directives">Scope of Definitions</a>, and also to show a means whereby the IBM-Style Local Values Support File can be incorporated at a <a href="#Global_Definitions">Global</a> level. Normally, <a href="#Multiple_device_nodes">that would be problematical</a> because the <a href="localvalues.html#Instance_Data_in_L_V_Support">Local Values Support functions</a> are written to use <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> data, in order to conserve use of System memory. By temporarily over-riding the definition of <span style="font-family: courier new,courier,monospace; font-weight: bold;">instance</span> in the <a href="#over_ride_instance">manner shown</a>, the User has traded-off economy of System-memory for convenience of programming. </p> <p>This example also offers an illustration of the use of <a href="#Shell_Env_Vbles_in_File_Names">Shell-Environment Variables in File-Names</a>: Let us suppose that the directory in which the main file for the controller of the assembly whose driver being compiled here resides in a directory-tree, several layers under the root. Immediately below the root is a sub-directory called <span style="font-family: courier new,courier,monospace; font-weight: bold;">shared</span> that contains shared functions and the Local Values support, and elsewhere under the tree are sharable bodies of driver code for device-modules that can be incorporated into various assemblies. Let us also suppose that the Makefile that governs this Tokenization process sets Environment Variables; the root of the tree is called <span style="font-family: courier new,courier,monospace; font-weight: bold;">DevRoot</span>, and the directory in which the sharable bodies reside are called <span style="font-family: courier new,courier,monospace; font-weight: bold;">SCZ</span> and <span style="font-family: courier new,courier,monospace; font-weight: bold;">SLZ</span> respectively. And let us further suppose that the <a href="#Example_4_Condl_FLoad">inclusion of these two subsidiary devices</a> is optional, controlled by command-line symbol definitions. </p> <div style="margin-left: 40px; color: rgb(68, 34, 0); font-family: courier new,courier,monospace;"> \ Define a few macros and functions that will become available<br> \ to all subordinate device-nodes in this bundle.<br> <br> \ Some of our functions are written using Local Values.<br> \ We can make the Local Values Support accessible Globally<br> \ without incurring any Warning messages, and without<br> \ altering the LocalValuesSupport file, if we temporarily<br> \ disable the definition of INSTANCE<br> <br> <span style="font-weight: bold;">fcode-version2</span><br> <br> <span style="font-weight: bold;">headers</span><br> <br> <span style="font-weight: bold;">global-definitions</span><br> <br> <a name="over_ride_instance"></a>\ Bypass warning about Instance<br> \ without altering LocalValuesSupport file<br> <br> \ Leave ourselves a way to recover<br> <span style="font-weight: bold;">alias</span> generic-instance instance<br> <br> \ Here's where we disable it. During development, give confirmation<br> \ that the macro has been activated by printing a message. Also,<br> \ insert a token in the place where the Instance would have<br> \ gone so that our detokenizations line up when we inspect. We<br> \ do this by defining a comand-line symbol called proto-code<br> \ For the final production run, we can make the macro completely<br> \ silent by leaving proto-code undefined.<br> <span style="font-weight: bold;">[ifdef]</span> proto-code<br> <span style="font-weight: bold;">overload [macro]</span> instance <span style="font-weight: bold;">message"</span> Bypassing Instance<span style="font-weight: bold;">"</span> <span style="font-weight: bold;">noop</span><br> <span style="font-weight: bold;">[else]</span><br> \ Make it completely silent<br> <span style="font-weight: bold;">overload [macro]</span> instance <span style="font-weight: bold;">f[ noop ]f</span><br> <span style="font-weight: bold;">[endif]</span><br> <br> <span style="font-weight: bold;">fload</span> ${DevRoot}/shared/<span style="font-weight: bold;">LocalValuesSupport.fth</span><br> <br> \ Restore normal meaning of Instance , also in Global scope.<br> <span style="font-weight: bold;">overload alias</span> instance generic-instance<br> <br> \ Here's a global definition that uses Local Values<br> : $CAT ( _max _str1 _len1 _str2 _len2 -- _max _str1 _len1' )<br> <span style="font-weight: bold;">{</span> _max _str1 _len1 _str2 _len2 <span style="font-weight: bold;">}</span><br> _len1 _max < if \ there is room<br> _str2 _str1 _len1 + _len2 _max _len1 - min move<br> then<br> _max _str1 _len1 _len2 + _max min \ always leave total length<br> ;<br> <br> \ Here is a global macro<br> <span style="font-weight: bold;">[macro]</span> 4DUP 2over 2over<br> <br> \ And another<br> <span style="font-weight: bold;">[macro]</span> 4DROP 2drop 2drop<br> <br> \ And yet another<br> <span style="font-weight: bold;">[macro]</span> (.h) base @ swap hex (.) rot base !<br> <br> \ Other shared functions are in a file in the Shared Code directory:<br> <span style="font-weight: bold;">fload</span> ${DevRoot}/shared/sharedfuncts.fth<br> <br> \ Definitions in all subsequent device-nodes will be able to access<br> \ the $CAT function and the macros 4DUP and 4DROP, as well as<br> \ to make use of IBM-Style Local Values without re-<span style="font-style: italic; font-weight: bold;">fload</span>ing<br> \ the Support File<br> <br> \ Now let's get back into the primary device-node.<br> <span style="font-weight: bold;">device-definitions</span><br> <br> \ Use instance data to create a large temporary buffer<br> d# 40 dup instance buffer: temp-buf ( max )<br> <br> \ Convolutions to create a name on the fly...<br> s" controller_" tuck ( max len adr len )<br> temp-buf swap ( max len adr buf len )<br> move ( max len )<br> temp-buf swap ( max buf len )<br> my-self (.h) ( max buf len adr2 len2 )<br> $cat ( max buf len )<br> device-name drop<br> <br> \ Make a macro of that. Define it in parts.<br> \ Requires the core of the name on the stack.<br> \ Macro will create its own temp-buf in the current device.<br> <br> <span style="font-weight: bold;">global-definitions<br> <br> </span>\ First part of the operation: ( adr len -- max adr len )<br> \ Note that "instance" is allowed here because it is not<br> \ invoked -- or even parsed -- until the macro is invoked.<br> <span style="font-weight: bold;">[macro]</span> create-buffr d# 40 dup instance buffer: temp-buf -rot<br> <br> \ Second part of the operation: ( max adr len -- max buf len )<br> <span style="font-weight: bold;">[macro]</span> name-to-buffr tuck temp-buf swap move temp-buf swap<br> <br> \ Last part of the operation: ( max buf len -- )<br> \ We're using my-self as part of the device-name<br> \ for no particularly good reason other than<br> \ that it makes for an interesting example... ;-}<br> <span style="font-weight: bold;">[macro]</span> buffr-to-dev-name my-self (.h) $cat device-name drop<br> <br> \ Combine the parts:<br> <span style="font-weight: bold;">[macro]</span> make-my-dev create-buffr name-to-buffr buffr-to-dev-name<br> <br> \ Back to the primary device-node.<br> <span style="font-weight: bold;">device-definitions</span><br> <br> \ Load its methods from the Current Directory<br> <span style="font-weight: bold;">fload</span> controller_methods.fth<br> <br> <a name="timestamp_prop"></a>\ Create timestamp property based on actual tokenization date and time<br> \ Combine into a single string (with a space between).<br> \ No trailing null-byte until end.<br> [fcode-date] encode-bytes " " encode-bytes encode+<br> [fcode-time] encode-string encode+ " release-time" property<br> <br> \ Log timestamp to the Audit Trail<br> tokenizer[ [fcode-date] [fcode-time] ]tokenizer<br> <br> <a name="Example_4_Condl_FLoad"></a>\ First optional subsidiary device. Inclusion controlled by command-line symbol.<br> <span style="font-weight: bold;">[ifdef]</span> scuzzy<br> <div style="margin-left: 40px;"><span style="font-weight: bold;">new-device</span><br> <br> " scuzzy_" make-my-dev<br> <br> \ Load its methods<br> <span style="font-weight: bold;">fload</span> ${SCZ}/scuzzy_methods.fth<br> <br> <span style="font-weight: bold;">finish-device</span><br> </div> <span style="font-weight: bold;">[endif]</span><br> <br> \ Second optional subsidiary device, controlled by command-line symbol.<br> <span style="font-weight: bold;">[ifdef]</span> sleazy<br> <div style="margin-left: 40px;"><span style="font-weight: bold;">new-device</span><br> <br> " sleazy_" make-my-dev<br> <br> \ Load its methods<br> <span style="font-weight: bold;">fload</span> ${SLZ}sleazy_methods.fth<br> <br> <span style="font-weight: bold;">finish-device</span><br> </div> <span style="font-weight: bold;">[endif]</span><br> <br> \ That's enough for now...<br> <span style="font-weight: bold;">fcode-end</span><br> </div> <h3><a class="mozTocH3" name="mozTocId866180"></a><a name="Example_5"></a>Example #5</h3> <p>This example serves to illustrate the use of the <a href="#function_name"><span style="font-family: courier new,courier,monospace; font-weight: bold;">[function-name]</span></a> directive to create a series of "you are here" debugging messages.<br> </p> <p>We will create a pair of macros whose names we can cut'n'paste at the beginning and end of every function we want to give a "you are here" message, switchable by a local debug-flag. The macros will be globally defined, but will make reference to locally-defined names for the debug-flag and the device-node name string. </p> <div style="margin-left: 40px; color: rgb(68, 34, 0); font-family: courier new,courier,monospace;"> <br> <span style="font-weight: bold;">fcode-version2</span><br> <br> <span style="font-weight: bold;">global-definitions</span><br> \ Each dev-node will create its own debug-flag and alias it to debug-me?<br> \ Each dev-node creates a macro called my-dev-name giving its device-name<br> <span style="font-weight: bold;"></span><br> <span style="font-weight: bold;">[macro]</span> .fname&dev <span style="font-weight: bold;">[function-name]</span> <span style="font-weight: bold;">type</span> <span style="font-weight: bold;">."</span> in <span style="font-weight: bold;">"</span> my-dev-name <span style="font-weight: bold;">type</span> <br> <br> <span style="font-weight: bold;">[macro]</span> name-my-dev my-dev-name <span style="font-weight: bold;">device-name<br> </span><br> <span style="font-weight: bold;">[macro]</span> .dbg-enter debug-me? <span style="font-weight: bold;">@</span> <span style="font-weight: bold;">if</span> <span style="font-weight: bold;">."</span> Entering<span style="font-weight: bold;"> "</span> .fname&dev <span style="font-weight: bold;">cr</span> <span style="font-weight: bold;">then</span><br> <span style="font-weight: bold;">[macro]</span> .dbg-leave debug-me? <span style="font-weight: bold;">@</span> <span style="font-weight: bold;">if</span> <span style="font-weight: bold;">."</span> Leaving <span style="font-weight: bold;">"</span> .fname&dev <span style="font-weight: bold;">cr</span> <span style="font-weight: bold;">then</span><br> <span style="font-weight: bold;">device-definitions</span><br> <br> <span style="font-weight: bold;">headers</span><br> \ Top-most device, named billy<br> <span style="font-weight: bold;">[macro]</span> my-dev-name " billy"<br> name-my-dev<br> <br> \ debug-billy? is a flag the user can turn "on" to get debug-messages<br> \ from the methods of the device we call "billy"<br> <span style="font-weight: bold;">variable</span> debug-billy? debug-billy? <span style="font-weight: bold;">off</span><br> \ Set it up for the macro<br> <span style="font-weight: bold;">alias</span> debug-me? debug-billy?<br> <br> : bill<br> .dbg-enter \ This will display Entering bill in billy<br> <span style="font-weight: bold;">[char]</span> G <span style="font-weight: bold;">dup</span><br> <span style="font-weight: bold;">control</span> G <span style="font-weight: bold;">3drop</span><br> .dbg-leave \ This will display Leaving bill in billy<br> <br> ;<br> <br> : factl recursive ( n -- n! )<br> <span style="font-weight: bold;">type</span> <span style="font-weight: bold;">."</span> Entering First vers. of <span style="font-weight: bold;">"</span> .fname&dev <span style="font-weight: bold;">cr</span><br> <span style="font-weight: bold;">?dup</span> <span style="font-weight: bold;">0=</span> <span style="font-weight: bold;">if</span> <span style="font-weight: bold;">1</span><br> <span style="font-weight: bold;">else</span> <span style="font-weight: bold;">dup</span> <span style="font-weight: bold;">1-</span> factl <span style="font-weight: bold;">*</span><br> <span style="font-weight: bold;">then</span><br> <span style="font-weight: bold;">."</span> Leaving First vers. of <span style="font-weight: bold;">"</span> .fname&dev <span style="font-weight: bold;">type</span> <span style="font-weight: bold;">cr</span><br> ;<br> <br> : factl ( n -- n! )<br> <span style="font-weight: bold;">type</span> <span style="font-weight: bold;">."</span> Entering Second vers. of <span style="font-weight: bold;">"</span> <span style="font-weight: bold;">[function-name]</span> <span style="font-weight: bold;">cr</span><br> <span style="font-weight: bold;">?dup</span> <span style="font-weight: bold;">0=</span> <span style="font-weight: bold;">if</span> <span style="font-weight: bold;">1</span> factl<br> <span style="font-weight: bold;">else</span> <span style="font-weight: bold;">dup</span> <span style="font-weight: bold;">1-</span> <span style="font-weight: bold;">recurse</span> <span style="font-weight: bold;">*</span><br> <span style="font-weight: bold;">then</span><br> <span style="font-weight: bold;">type</span> <span style="font-weight: bold;">."</span> Leaving Second vers. of <span style="font-weight: bold;">"</span> <span style="font-weight: bold;">[function-name]</span> <span style="font-weight: bold;">cr</span><br> ;<br> <br> <span style="font-weight: bold;">variable</span> naught<br> <span style="font-weight: bold;">defer</span> do-nothing<br> 20 <span style="font-weight: bold;">value</span> twenty<br> 30 <span style="font-weight: bold;">value</span> thirty<br> 40 <span style="font-weight: bold;">buffer:</span> forty<br> 50 <span style="font-weight: bold;">constant</span> fifty<br> <span style="font-weight: bold;">create</span> three 0 <span style="font-weight: bold;">,</span> 00 <span style="font-weight: bold;">,</span> <span style="font-weight: bold;">h#</span> 000 <span style="font-weight: bold;">,</span><br> <span style="font-weight: bold;">struct</span><br> 4 <span style="font-weight: bold;">field</span> >four<br> <span style="font-weight: bold;">constant</span> /four<br> <br> : peril<br> .dbg-enter \ This will display Entering peril in billy<br> <span style="font-weight: bold;">[']</span> <span style="font-weight: bold;">noop</span> <span style="font-weight: bold;">to</span> do-nothing<br> 100 <span style="font-weight: bold;">to</span> thirty<br> 5 <span style="font-weight: bold;">to</span> naught <span style="font-style: italic;">\ Generates a WARNING</span><br> thirty <span style="font-weight: bold;">dup</span> <span style="font-weight: bold;">-</span> <span style="font-weight: bold;">abort"</span> Never Happen<span style="font-weight: bold;">"</span><br> .dbg-leave \ You get the idea...<br> ;<br> <br> : thirty ( new-val -- )<br> .dbg-enter<br> <span style="font-weight: bold;">dup</span> <span style="font-weight: bold;">to</span> thirty<br> <span style="font-weight: bold;">alias</span> .dec <span style="font-weight: bold;">.d</span> \ Generates a WARNING and an ADVISORY<br> ." Dirty" .dec<br> .dbg-leave<br> ;<br> <br> \ First subsidiary device, "child" of billy<br> <span style="font-weight: bold;">new-device</span><br> <span style="font-weight: bold;">instance</span> <span style="font-weight: bold;">variable</span> cheryl<br> <span style="font-weight: bold;">[macro]</span> my-dev-name <span style="font-weight: bold;">"</span> cheryl<span style="font-weight: bold;">"</span><br> name-my-dev<br> <br> \ Third-level device, "grandchild" of billy<br> <span style="font-weight: bold;">new-device</span><br> <span style="font-weight: bold;">[macro]</span> my-dev-name <span style="font-weight: bold;">"</span> meryl<span style="font-weight: bold;">"</span><br> name-my-dev<br> <span style="font-weight: bold;">variable</span> debug-meryl? debug-meryl? <span style="font-weight: bold;">off</span><br> <span style="font-weight: bold;">alias</span> debug-me? debug-meryl?<br> <br> : merle<br> .dbg-enter \ This will display Entering merle in meryl<br> cheryl \ ERROR. Is in a different dev-node.<br> .dbg-leave<br> ;<br> <span style="font-weight: bold;">variable</span> beryl<br> <span style="font-weight: bold;">finish-device</span><br> <br> \ Now we're back to "cheryl"<br> <br> <span style="font-weight: bold;">variable</span> debug-cheryl? debug-cheryl? <span style="font-weight: bold;">off</span><br> alias debug-me? debug-cheryl?<br> <br> : queryl<br> .dbg-enter \ This will display Entering queryl in cheryl<br> <span style="font-weight: bold; font-style: italic;">over rot dup nip drop swap</span> \ Not the most useful code... ;-}<br> .dbg-leave<br> ;<br> <span style="font-weight: bold;">finish-device</span><br> \ And we're back to billy.<br> : droop ( -- )<br> .dbg-enter \ This will display Entering droop in billy<br> twenty<br> 0 <span style="font-weight: bold;">?do</span> i .h <span style="font-weight: bold;">loop</span><br> .dbg-leave \ You get the idea....<br> ;<br> <br> <a name="Example_5_func_nam"></a><br> \ The following will generate some unexpected errors:<br> : quack ( maybe not -- oops! I-forgot-the-close-paren<br> .dbg-enter \ This should display Entering quack in billy<br> \ But it doesn't display anything and I don't know why.<br> h# 30 .d<br> .dbg-leave \ and I'm still baffled...<br> ; \ Oh, well, soldier on...<br> : cluck ( don't count -- before hatched ) \ Now, <span style="font-style: italic;">there's</span> a close-paren.... </div> <br> <div style="color: black; font-family: helvetica,arial,sans-serif; font-weight: bold;"><span style="font-style: italic;">Note:</span> At this point, the Tokenizer has issued a <a href="#Allow_Multi_Line">Multi-Line Warning</a> about a Comment that began six lines earlier, which gives the User a good indication as to just what went wrong... </div> <br> <div style="margin-left: 40px; color: rgb(68, 34, 0); font-family: courier new,courier,monospace;"> .dbg-enter \ This does display, but not what I expected.<br> ." Coming from" <a href="#Inp_Fil_Nm_Strg">[input-file-name]</a> type ." line " <a href="#Inp_Fil_Nm_Strg">[line-number]</a> .d cr<br> tokenizer[ <a href="#function_name">[function-name]</a> ]tokenizer \ Let's not wait for run-time<br> .dbg-leave \ Now I get it...<br> ;<br> <span style="font-weight: bold;">fcode-end</span><br> <br> </div> <br> <h2><a class="mozTocH2" name="mozTocId856440"></a>End Of Document</h2> <!-- =========================================================================== --> </body> </html>