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kc3-lang/automake/lib/Automake/Condition.pm
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Alexandre Duret-Lutz
Date : 2005-05-14 20:28:56
Hash : 1183efd3
Message : * COPYING, ChangeLog, ChangeLog.00, ChangeLog.01, ChangeLog.02, ChangeLog.03, ChangeLog.96, ChangeLog.98, HACKING, Makefile.am, NEWS, README, TODO, aclocal.in, automake.in, bootstrap, configure, configure.ac, doc/Makefile.am, doc/fdl.texi, lib/COPYING, lib/Makefile.am, lib/acinstall, lib/compile, lib/config-ml.in, lib/config.guess, lib/config.sub, lib/depcomp, lib/elisp-comp, lib/gnupload, lib/mdate-sh, lib/missing, lib/py-compile, lib/symlink-tree, lib/texinfo.tex, lib/ylwrap, lib/Automake/ChannelDefs.pm, lib/Automake/Channels.pm, lib/Automake/Condition.pm, lib/Automake/Config.in, lib/Automake/Configure_ac.pm, lib/Automake/DisjConditions.pm, lib/Automake/FileUtils.pm, lib/Automake/General.pm, lib/Automake/Item.pm, lib/Automake/ItemDef.pm, lib/Automake/Location.pm, lib/Automake/Makefile.am, lib/Automake/Options.pm, lib/Automake/Rule.pm, lib/Automake/RuleDef.pm, lib/Automake/Struct.pm, lib/Automake/VarDef.pm, lib/Automake/Variable.pm, lib/Automake/Version.pm, lib/Automake/Wrap.pm, lib/Automake/XFile.pm, lib/Automake/tests/Condition.pl, lib/Automake/tests/DisjConditions.pl, lib/Automake/tests/Makefile.am, lib/Automake/tests/Version.pl, lib/Automake/tests/Wrap.pl, lib/am/Makefile.am, lib/am/ansi2knr.am, lib/am/check.am, lib/am/clean-hdr.am, lib/am/clean.am, lib/am/compile.am, lib/am/configure.am, lib/am/data.am, lib/am/dejagnu.am, lib/am/depend.am, lib/am/depend2.am, lib/am/distdir.am, lib/am/footer.am, lib/am/header-vars.am, lib/am/header.am, lib/am/inst-vars.am, lib/am/install.am, lib/am/java.am, lib/am/lang-compile.am, lib/am/lex.am, lib/am/library.am, lib/am/libs.am, lib/am/libtool.am, lib/am/lisp.am, lib/am/ltlib.am, lib/am/ltlibrary.am, lib/am/mans-vars.am, lib/am/mans.am, lib/am/multilib.am, lib/am/program.am, lib/am/progs.am, lib/am/python.am, lib/am/remake-hdr.am, lib/am/scripts.am, lib/am/subdirs.am, lib/am/tags.am, lib/am/texi-vers.am, lib/am/texibuild.am, lib/am/texinfos.am, lib/am/yacc.am, m4/Makefile.am, tests/aclibobj.test, tests/acloca10.test, tests/acloca11.test, tests/acloca12.test, tests/acloca13.test, tests/acloca14.test, tests/acloca15.test, tests/acloca16.test, tests/acloca17.test, tests/acloca18.test, tests/acloca19.test, tests/aclocal.test, tests/aclocal3.test, tests/aclocal4.test, tests/aclocal5.test, tests/aclocal6.test, tests/aclocal7.test, tests/aclocal8.test, tests/aclocal9.test, tests/acoutbs.test, tests/acoutbs2.test, tests/acoutnoq.test, tests/acoutpt.test, tests/acoutpt2.test, tests/acoutqnl.test, tests/acsilent.test, tests/acsubst.test, tests/acsubst2.test, tests/all.test, tests/alloca.test, tests/alloca2.test, tests/alpha.test, tests/alpha2.test, tests/amassign.test, tests/ammissing.test, tests/ansi.test, tests/ansi10.test, tests/ansi2.test, tests/ansi3.test, tests/ansi3b.test, tests/ansi4.test, tests/ansi5.test, tests/ansi6.test, tests/ansi7.test, tests/ansi8.test, tests/ansi9.test, tests/ar.test, tests/ar2.test, tests/asm.test, tests/autohdr.test, tests/autohdr2.test, tests/autohdr3.test, tests/autohdr4.test, tests/automake.test, tests/auxdir.test, tests/auxdir2.test, tests/auxdir3.test, tests/auxdir4.test, tests/backsl.test, tests/backsl2.test, tests/backsl3.test, tests/backsl4.test, tests/badline.test, tests/badopt.test, tests/badprog.test, tests/block.test, tests/bsource.test, tests/canon.test, tests/canon2.test, tests/canon3.test, tests/canon4.test, tests/canon5.test, tests/ccnoco.test, tests/check.test, tests/check2.test, tests/check3.test, tests/check4.test, tests/checkall.test, tests/clean.test, tests/clean2.test, tests/colneq.test, tests/colneq2.test, tests/colon.test, tests/colon2.test, tests/colon3.test, tests/colon4.test, tests/colon5.test, tests/colon6.test, tests/colon7.test, tests/comment.test, tests/comment2.test, tests/comment3.test, tests/comment4.test, tests/comment5.test, tests/comment6.test, tests/comment7.test, tests/comment8.test, tests/comment9.test, tests/compile.test, tests/compile_f90_c_cxx.test, tests/compile_f_c_cxx.test, tests/cond.test, tests/cond10.test, tests/cond11.test, tests/cond13.test, tests/cond14.test, tests/cond15.test, tests/cond16.test, tests/cond17.test, tests/cond18.test, tests/cond19.test, tests/cond2.test, tests/cond20.test, tests/cond21.test, tests/cond22.test, tests/cond23.test, tests/cond24.test, tests/cond25.test, tests/cond26.test, tests/cond27.test, tests/cond28.test, tests/cond29.test, tests/cond3.test, tests/cond30.test, tests/cond31.test, tests/cond32.test, tests/cond33.test, tests/cond34.test, tests/cond35.test, tests/cond36.test, tests/cond37.test, tests/cond4.test, tests/cond5.test, tests/cond6.test, tests/cond7.test, tests/cond8.test, tests/cond9.test, tests/condd.test, tests/condhook.test, tests/condinc.test, tests/condinc2.test, tests/condlib.test, tests/condman.test, tests/condman2.test, tests/conf2.test, tests/confdeps.test, tests/conff.test, tests/conff2.test, tests/confh.test, tests/confh4.test, tests/confh5.test, tests/config.test, tests/confincl.test, tests/conflnk.test, tests/conflnk2.test, tests/conflnk3.test, tests/confsub.test, tests/confvar.test, tests/confvar2.test, tests/copy.test, tests/ctarget1.test, tests/cxx.test, tests/cxx2.test, tests/cxxansi.test, tests/cxxcpp.test, tests/cxxlibobj.test, tests/cxxlink.test, tests/cxxnoc.test, tests/cxxo.test, tests/cygwin32.test, tests/dash.test, tests/defs.in, tests/defun.test, tests/defun2.test, tests/dejagnu.test, tests/dejagnu2.test, tests/dejagnu3.test, tests/dejagnu4.test, tests/dejagnu5.test, tests/dejagnu6.test, tests/dejagnu7.test, tests/depacl2.test, tests/depcomp.test, tests/depcomp2.test, tests/depcomp3.test, tests/depcomp4.test, tests/depcomp5.test, tests/depdist.test, tests/depend.test, tests/depend2.test, tests/depend3.test, tests/depend4.test, tests/destdir.test, tests/dirforbid.test, tests/dirlist.test, tests/discover.test, tests/distcom2.test, tests/distcom3.test, tests/distcom4.test, tests/distcom5.test, tests/distcom6.test, tests/distcom7.test, tests/distdir.test, tests/distname.test, tests/dollar.test, tests/double.test, tests/dup2.test, tests/else.test, tests/empty.test, tests/empty2.test, tests/empty3.test, tests/empty4.test, tests/exdir.test, tests/exdir2.test, tests/exeext.test, tests/exeext2.test, tests/exeext3.test, tests/exeext4.test, tests/exsource.test, tests/ext.test, tests/ext2.test, tests/extra.test, tests/extra2.test, tests/extra3.test, tests/extra4.test, tests/extra5.test, tests/extra6.test, tests/extra7.test, tests/f90only.test, tests/flibs.test, tests/fn99.test, tests/fnoc.test, tests/fo.test, tests/fonly.test, tests/fortdep.test, tests/fpinst2.test, tests/fpinstall.test, tests/gcj.test, tests/gcj2.test, tests/gcj3.test, tests/gcj4.test, tests/gcj5.test, tests/getopt.test, tests/gettext.test, tests/gettext2.test, tests/gnits.test, tests/gnits2.test, tests/gnits3.test, tests/gnumake.test, tests/gnuwarn.test, tests/gnuwarn2.test, tests/header.test, tests/help.test, tests/hfs.test, tests/hosts.test, tests/implicit.test, tests/include.test, tests/include2.test, tests/info.test, tests/insh2.test, tests/install2.test, tests/installdir.test, tests/instdat.test, tests/instdat2.test, tests/instexec.test, tests/insthook.test, tests/instman.test, tests/instman2.test, tests/instsh.test, tests/instsh2.test, tests/instspc.test, tests/interp.test, tests/interp2.test, tests/java.test, tests/java2.test, tests/java3.test, tests/javaprim.test, tests/javasubst.test, tests/ldadd.test, tests/ldflags.test, tests/lex.test, tests/lex2.test, tests/lex3.test, tests/lex4.test, tests/lex5.test, tests/libobj10.test, tests/libobj11.test, tests/libobj12.test, tests/libobj13.test, tests/libobj14.test, tests/libobj2.test, tests/libobj3.test, tests/libobj4.test, tests/libobj5.test, tests/libobj7.test, tests/libobj8.test, tests/library.test, tests/library2.test, tests/library3.test, tests/libtool.test, tests/libtool2.test, tests/libtool3.test, tests/libtool4.test, tests/libtool5.test, tests/libtool6.test, tests/libtool7.test, tests/libtool8.test, tests/libtool9.test, tests/license.test, tests/link_c_cxx.test, tests/link_dist.test, tests/link_f90_only.test, tests/link_f_only.test, tests/link_fc.test, tests/link_fccxx.test, tests/link_fcxx.test, tests/lisp2.test, tests/lisp3.test, tests/lisp4.test, tests/lisp5.test, tests/lisp6.test, tests/lisp7.test, tests/lisp8.test, tests/listval.test, tests/location.test, tests/longlin2.test, tests/longline.test, tests/ltcond.test, tests/ltcond2.test, tests/ltconv.test, tests/ltdeps.test, tests/ltlibobjs.test, tests/ltlibsrc.test, tests/maintclean.test, tests/make.test, tests/makej.test, tests/makevars.test, tests/man.test, tests/man2.test, tests/mclean.test, tests/mdate.test, tests/mdate2.test, tests/mdate3.test, tests/mdate4.test, tests/missing.test, tests/missing2.test, tests/missing3.test, tests/mkinst2.test, tests/mkinstall.test, tests/mmodely.test, tests/multlib.test, tests/nobase.test, tests/nodef.test, tests/nodef2.test, tests/nodep.test, tests/nodepcomp.test, tests/nodist.test, tests/nodist2.test, tests/nodist3.test, tests/nogzip.test, tests/nogzip2.test, tests/noinst.test, tests/noinstdir.test, tests/nolink.test, tests/nostdinc.test, tests/number.test, tests/obsolete.test, tests/order.test, tests/outdir.test, tests/output.test, tests/output10.test, tests/output11.test, tests/output12.test, tests/output2.test, tests/output3.test, tests/output4.test, tests/output5.test, tests/output6.test, tests/output7.test, tests/output8.test, tests/output9.test, tests/overrid.test, tests/parse.test, tests/percent.test, tests/percent2.test, tests/phony.test, tests/pluseq.test, tests/pluseq10.test, tests/pluseq2.test, tests/pluseq3.test, tests/pluseq4.test, tests/pluseq5.test, tests/pluseq6.test, tests/pluseq7.test, tests/pluseq8.test, tests/pluseq9.test, tests/postproc.test, tests/ppf77.test, tests/pr2.test, tests/pr204.test, tests/pr211.test, tests/pr220.test, tests/pr224.test, tests/pr229.test, tests/pr243.test, tests/pr266.test, tests/pr279-2.test, tests/pr279.test, tests/pr287.test, tests/pr300-lib.test, tests/pr300-ltlib.test, tests/pr300-prog.test, tests/pr307.test, tests/pr401.test, tests/pr401b.test, tests/pr401c.test, tests/pr72.test, tests/pr87.test, tests/pr9.test, tests/prefix.test, tests/primary.test, tests/primary2.test, tests/primary3.test, tests/proginst.test, tests/python.test, tests/python10.test, tests/python11.test, tests/python12.test, tests/python2.test, tests/python3.test, tests/python4.test, tests/python5.test, tests/python6.test, tests/python7.test, tests/python8.test, tests/python9.test, tests/recurs.test, tests/recurs2.test, tests/regex.test, tests/remake.test, tests/remake2.test, tests/remake3.test, tests/remake4.test, tests/remake5.test, tests/req.test, tests/reqd.test, tests/reqd2.test, tests/rulepat.test, tests/scripts.test, tests/seenc.test, tests/sinclude.test, tests/space.test, tests/specflg.test, tests/specflg2.test, tests/specflg3.test, tests/specflg6.test, tests/specflg7.test, tests/specflg8.test, tests/specflg9.test, tests/spell.test, tests/spell2.test, tests/spell3.test, tests/spelling.test, tests/spy.test, tests/srcsub.test, tests/srcsub2.test, tests/stamph2.test, tests/stdlib.test, tests/stdlib2.test, tests/strip.test, tests/subcond.test, tests/subcond2.test, tests/subcond3.test, tests/subdir.test, tests/subdir2.test, tests/subdir3.test, tests/subdir4.test, tests/subdir5.test, tests/subdir6.test, tests/subdir7.test, tests/subdir8.test, tests/subdir9.test, tests/subdirbuiltsources.test, tests/subobj.test, tests/subobj2.test, tests/subobj3.test, tests/subobj4.test, tests/subobj5.test, tests/subobj6.test, tests/subobj7.test, tests/subobj8.test, tests/subobj9.test, tests/subobjname.test, tests/subpkg.test, tests/subpkg2.test, tests/subst.test, tests/subst2.test, tests/substre2.test, tests/substref.test, tests/substtarg.test, tests/suffix.test, tests/suffix10.test, tests/suffix11.test, tests/suffix2.test, tests/suffix3.test, tests/suffix4.test, tests/suffix5.test, tests/suffix6.test, tests/suffix7.test, tests/suffix8.test, tests/suffix9.test, tests/symlink.test, tests/symlink2.test, tests/symlink3.test, tests/syntax.test, tests/tags.test, tests/tagsub.test, tests/tar.test, tests/tar2.test, tests/tar3.test, tests/target-cflags.test, tests/targetclash.test, tests/transform.test, tests/txinfo.test, tests/txinfo10.test, tests/txinfo13.test, tests/txinfo16.test, tests/txinfo17.test, tests/txinfo18.test, tests/txinfo19.test, tests/txinfo2.test, tests/txinfo20.test, tests/txinfo21.test, tests/txinfo22.test, tests/txinfo23.test, tests/txinfo24.test, tests/txinfo25.test, tests/txinfo26.test, tests/txinfo27.test, tests/txinfo28.test, tests/txinfo29.test, tests/txinfo3.test, tests/txinfo4.test, tests/txinfo5.test, tests/txinfo6.test, tests/txinfo7.test, tests/txinfo8.test, tests/txinfo9.test, tests/unused.test, tests/vars.test, tests/vars3.test, tests/vartar.test, tests/version.test, tests/version2.test, tests/version3.test, tests/version4.test, tests/version6.test, tests/version7.test, tests/version8.test, tests/vpath.test, tests/vtexi.test, tests/vtexi2.test, tests/warnopts.test, tests/werror.test, tests/werror2.test, tests/whoami.test, tests/xsource.test, tests/yacc.test, tests/yacc2.test, tests/yacc3.test, tests/yacc4.test, tests/yacc5.test, tests/yacc6.test, tests/yacc7.test, tests/yacc8.test, tests/yaccpp.test, tests/yaccvpath.test: Update FSF postal mail address.
- lib/Automake/Condition.pm
-
# Copyright (C) 1997, 2001, 2002, 2003 Free Software Foundation, Inc. # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2, or (at your option) # any later version. # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # You should have received a copy of the GNU General Public License # along with this program; if not, write to the Free Software # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA # 02110-1301, USA. package Automake::Condition; use strict; use Carp; require Exporter; use vars '@ISA', '@EXPORT_OK'; @ISA = qw/Exporter/; @EXPORT_OK = qw/TRUE FALSE reduce_and reduce_or/; =head1 NAME Automake::Condition - record a conjunction of conditionals =head1 SYNOPSIS use Automake::Condition; # Create a condition to represent "COND1 and not COND2". my $cond = new Automake::Condition "COND1_TRUE", "COND2_FALSE"; # Create a condition to represent "not COND3". my $other = new Automake::Condition "COND3_FALSE"; # Create a condition to represent # "COND1 and not COND2 and not COND3". my $both = $cond->merge ($other); # Likewise, but using a list of conditional strings my $both2 = $cond->merge_conds ("COND3_FALSE"); # Strip from $both any subconditions which are in $other. # This is the opposite of merge. $cond = $both->strip ($other); # Return the list of conditions ("COND1_TRUE", "COND2_FALSE"): my @conds = $cond->conds; # Is $cond always true? (Not in this example) if ($cond->true) { ... } # Is $cond always false? (Not in this example) if ($cond->false) { ... } # Return the list of conditionals as a string: # "COND1_TRUE COND2_FALSE" my $str = $cond->string; # Return the list of conditionals as a human readable string: # "COND1 and !COND2" my $str = $cond->human; # Return the list of conditionals as a AC_SUBST-style string: # "@COND1_TRUE@@COND2_FALSE@" my $subst = $cond->subst_string; # Is $cond true when $both is true? (Yes in this example) if ($cond->true_when ($both)) { ... } # Is $cond redundant w.r.t. {$other, $both}? # (Yes in this example) if ($cond->redundant_wrt ($other, $both)) { ... } # Does $cond imply any of {$other, $both}? # (Not in this example) if ($cond->implies_any ($other, $both)) { ... } # Remove superfluous conditionals assuming they will eventually # be multiplied together. # (Returns @conds = ($both) in this example, because # $other and $cond are implied by $both.) @conds = Automake::Condition::reduce_and ($other, $both, $cond); # Remove superfluous conditionals assuming they will eventually # be summed together. # (Returns @conds = ($cond, $other) in this example, because # $both is a subset condition of $cond: $cond is true whenever $both # is true.) @conds = Automake::Condition::reduce_or ($other, $both, $cond); # Invert a Condition. This returns a list of Conditions. @conds = $both->not; =head1 DESCRIPTION A C<Condition> is a conjunction of conditionals (i.e., atomic conditions defined in F<configure.ac> by C<AM_CONDITIONAL>. In Automake they are used to represent the conditions into which F<Makefile> variables and F<Makefile> rules are defined. If the variable C<VAR> is defined as if COND1 if COND2 VAR = value endif endif then it will be associated a C<Condition> created with the following statement. new Automake::Condition "COND1_TRUE", "COND2_TRUE"; Remember that a C<Condition> is a I<conjunction> of conditionals, so the above C<Condition> means C<VAR> is defined when C<COND1> B<and> C<COND2> are true. There is no way to express disjunctions (i.e., I<or>s) with this class (but see L<DisjConditions>). Another point worth to mention is that each C<Condition> object is unique with respect to its conditionals. Two C<Condition> objects created for the same set of conditionals will have the same adress. This makes it easy to compare C<Condition>s, just compare the references. my $c1 = new Automake::Condition "COND1_TRUE", "COND2_TRUE"; my $c2 = new Automake::Condition "COND1_TRUE", "COND2_TRUE"; $c1 == $c2; # True! =head2 Methods =over 4 =item C<$cond = new Automake::Condition [@conds]> Return a C<Condition> objects for the conjunctions of conditionals listed in C<@conds> as strings. An item in C<@conds> should be either C<"FALSE">, C<"TRUE">, or have the form C<"NAME_FALSE"> or C<"NAME_TRUE"> where C<NAME> can be anything (in practice C<NAME> should be the name of a conditional declared in F<configure.ac> with C<AM_CONDITIONAL>, but it's not C<Automake::Condition>'s responsability to ensure this). An empty C<@conds> means C<"TRUE">. As explained previously, the reference (object) returned is unique with respect to C<@conds>. For this purpose, duplicate elements are ignored, and C<@conds> is rewriten as C<("FALSE")> if it contains C<"FALSE"> or two contradictory conditionals (such as C<"NAME_FALSE"> and C<"NAME_TRUE">.) Therefore the following two statements create the same object (they both create the C<"FALSE"> condition). my $c3 = new Automake::Condition "COND1_TRUE", "COND1_FALSE"; my $c4 = new Automake::Condition "COND2_TRUE", "FALSE"; $c3 == $c4; # True! $c3 == FALSE; # True! =cut # Keys in this hash are conditional strings. Values are the # associated object conditions. This is used by `new' to reuse # Condition objects with identical conditionals. use vars '%_condition_singletons'; # Do NOT reset this hash here. It's already empty by default, # and any setting would otherwise occur AFTER the `TRUE' and `FALSE' # constants definitions. # %_condition_singletons = (); sub new ($;@) { my ($class, @conds) = @_; my $self = { hash => {}, }; bless $self, $class; # Accept strings like "FOO BAR" as shorthand for ("FOO", "BAR"). @conds = map { split (' ', $_) } @conds; for my $cond (@conds) { next if $cond eq 'TRUE'; # Catch some common programming errors: # - A Condition passed to new confess "`$cond' is a reference, expected a string" if ref $cond; # - A Condition passed as a string to new confess "`$cond' does not look like a condition" if $cond =~ /::/; # Detect cases when @conds can be simplified to FALSE. if (($cond eq 'FALSE' && $#conds > 0) || ($cond =~ /^(.*)_TRUE$/ && exists $self->{'hash'}{"${1}_FALSE"}) || ($cond =~ /^(.*)_FALSE$/ && exists $self->{'hash'}{"${1}_TRUE"})) { return &FALSE; } $self->{'hash'}{$cond} = 1; } my $key = $self->string; if (exists $_condition_singletons{$key}) { return $_condition_singletons{$key}; } $_condition_singletons{$key} = $self; return $self; } =item C<$newcond = $cond-E<gt>merge (@otherconds)> Return a new condition which is the conjunction of C<$cond> and C<@otherconds>. =cut sub merge ($@) { my ($self, @otherconds) = @_; new Automake::Condition (map { $_->conds } ($self, @otherconds)); } =item C<$newcond = $cond-E<gt>merge_conds (@conds)> Return a new condition which is the conjunction of C<$cond> and C<@conds>, where C<@conds> is a list of conditional strings, as passed to C<new>. =cut sub merge_conds ($@) { my ($self, @conds) = @_; new Automake::Condition $self->conds, @conds; } =item C<$newcond = $cond-E<gt>strip ($minuscond)> Return a new condition which has all the conditionals of C<$cond> except those of C<$minuscond>. This is the opposite of C<merge>. =cut sub strip ($$) { my ($self, $minus) = @_; my @res = grep { not $minus->has ($_) } $self->conds; return new Automake::Condition @res; } =item C<@list = $cond-E<gt>conds> Return the set of conditionals defining C<$cond>, as strings. Note that this might not be exactly the list passed to C<new> (or a concatenation of such lists if C<merge> was used), because of the cleanup mentioned in C<new>'s description. For instance C<$c3-E<gt>conds> will simply return C<("FALSE")>. =cut sub conds ($ ) { my ($self) = @_; my @conds = keys %{$self->{'hash'}}; return ("TRUE") unless @conds; return sort @conds; } # Undocumented, shouldn't be needed out of this class. sub has ($$) { my ($self, $cond) = @_; return exists $self->{'hash'}{$cond}; } =item C<$cond-E<gt>false> Return 1 iff this condition is always false. =cut sub false ($ ) { my ($self) = @_; return $self->has ('FALSE'); } =item C<$cond-E<gt>true> Return 1 iff this condition is always true. =cut sub true ($ ) { my ($self) = @_; return 0 == keys %{$self->{'hash'}}; } =item C<$cond-E<gt>string> Build a string which denotes the condition. For instance using the C<$cond> definition from L<SYNOPSYS>, C<$cond-E<gt>string> will return C<"COND1_TRUE COND2_FALSE">. =cut sub string ($ ) { my ($self) = @_; return $self->{'string'} if defined $self->{'string'}; my $res = ''; if ($self->false) { $res = 'FALSE'; } else { $res = join (' ', $self->conds); } $self->{'string'} = $res; return $res; } =item C<$cond-E<gt>human> Build a human readable string which denotes the condition. For instance using the C<$cond> definition from L<SYNOPSYS>, C<$cond-E<gt>string> will return C<"COND1 and !COND2">. =cut sub _to_human ($ ) { my ($s) = @_; if ($s =~ /^(.*)_(TRUE|FALSE)$/) { return (($2 eq 'FALSE') ? '!' : '') . $1; } else { return $s; } } sub human ($ ) { my ($self) = @_; return $self->{'human'} if defined $self->{'human'}; my $res = ''; if ($self->false) { $res = 'FALSE'; } else { $res = join (' and ', map { _to_human $_ } $self->conds); } $self->{'human'} = $res; return $res; } =item C<$cond-E<gt>subst_string> Build a C<AC_SUBST>-style string for output in F<Makefile.in>. For instance using the C<$cond> definition from L<SYNOPSYS>, C<$cond-E<gt>subst_string> will return C<"@COND1_TRUE@@COND2_FALSE@">. =cut sub subst_string ($ ) { my ($self) = @_; return $self->{'subst_string'} if defined $self->{'subst_string'}; my $res = ''; if ($self->false) { $res = '#'; } elsif (! $self->true) { $res = '@' . join ('@@', sort $self->conds) . '@'; } $self->{'subst_string'} = $res; return $res; } =item C<$cond-E<gt>true_when ($when)> Return 1 iff C<$cond> is true when C<$when> is true. Return 0 otherwise. Using the definitions from L<SYNOPSYS>, C<$cond> is true when C<$both> is true, but the converse is wrong. =cut sub true_when ($$) { my ($self, $when) = @_; # Nothing is true when FALSE (not even FALSE itself, but it # shouldn't hurt if you decide to change that). return 0 if $self->false || $when->false; # If we are true, we stay true when $when is true :) return 1 if $self->true; # $SELF is true under $WHEN if each conditional component of $SELF # exists in $WHEN. foreach my $cond ($self->conds) { return 0 unless $when->has ($cond); } return 1; } =item C<$cond-E<gt>redundant_wrt (@conds)> Return 1 iff C<$cond> is true for any condition in C<@conds>. If @conds is empty, return 1 iff C<$cond> is C<FALSE>. Return 0 otherwise. =cut sub redundant_wrt ($@) { my ($self, @conds) = @_; foreach my $cond (@conds) { return 1 if $self->true_when ($cond); } return $self->false; } =item C<$cond-E<gt>implies_any (@conds)> Return 1 iff C<$cond> implies any of the conditions in C<@conds>. Return 0 otherwise. =cut sub implies_any ($@) { my ($self, @conds) = @_; foreach my $cond (@conds) { return 1 if $cond->true_when ($self); } return 0; } =item C<$cond-E<gt>not> Return a negation of C<$cond> as a list of C<Condition>s. This list should be used to construct a C<DisjConditions> (we cannot return a C<DisjConditions> from C<Automake::Condition>, because that would make these two packages interdependent). =cut sub not ($ ) { my ($self) = @_; return @{$self->{'not'}} if defined $self->{'not'}; my @res = map { new Automake::Condition &conditional_negate ($_) } $self->conds; $self->{'not'} = [@res]; return @res; } =item C<$cond-E<gt>multiply (@conds)> Assumption: C<@conds> represent a disjunction of conditions. Return the result of multiplying C<$cond> with that disjunction. The result will be a list of conditions suitable to construct a C<DisjConditions>. =cut sub multiply ($@) { my ($self, @set) = @_; my %res = (); for my $cond (@set) { my $ans = $self->merge ($cond); $res{$ans} = $ans; } # FALSE can always be removed from a disjunction. delete $res{FALSE}; # Now, $self is a common factor of the remaining conditions. # If one of the conditions is $self, we can discard the rest. return ($self, ()) if exists $res{$self}; return (values %res); } =head2 Other helper functions =over 4 =item C<TRUE> The C<"TRUE"> conditional. =item C<FALSE> The C<"FALSE"> conditional. =cut use constant TRUE => new Automake::Condition "TRUE"; use constant FALSE => new Automake::Condition "FALSE"; =item C<reduce_and (@conds)> Return a subset of @conds with the property that the conjunction of the subset is the same as the conjunction of @conds. For example, if both C<COND1_TRUE COND2_TRUE> and C<COND1_TRUE> are in the list, discard the latter. If the input list is empty, return C<(TRUE)>. =cut sub reduce_and (@) { my (@conds) = @_; my @ret = (); my $cond; while (@conds > 0) { $cond = shift @conds; # FALSE is absorbent. return FALSE if $cond == FALSE; if (! $cond->redundant_wrt (@ret, @conds)) { push (@ret, $cond); } } return TRUE if @ret == 0; return @ret; } =item C<reduce_or (@conds)> Return a subset of @conds with the property that the disjunction of the subset is equivalent to the disjunction of @conds. For example, if both C<COND1_TRUE COND2_TRUE> and C<COND1_TRUE> are in the list, discard the former. If the input list is empty, return C<(FALSE)>. =cut sub reduce_or (@) { my (@conds) = @_; my @ret = (); my $cond; while (@conds > 0) { $cond = shift @conds; next if $cond == FALSE; return TRUE if $cond == TRUE; push (@ret, $cond) unless $cond->implies_any (@ret, @conds); } return FALSE if @ret == 0; return @ret; } =item C<conditional_negate ($condstr)> Negate a conditional string. =cut sub conditional_negate ($) { my ($cond) = @_; $cond =~ s/TRUE$/TRUEO/; $cond =~ s/FALSE$/TRUE/; $cond =~ s/TRUEO$/FALSE/; return $cond; } =head1 SEE ALSO L<Automake::DisjConditions>. =head1 HISTORY C<AM_CONDITIONAL>s and supporting code were added to Automake 1.1o by Ian Lance Taylor <ian@cygnus.org> in 1997. Since then it has been improved by Tom Tromey <tromey@redhat.com>, Richard Boulton <richard@tartarus.org>, Raja R Harinath <harinath@cs.umn.edu>, Akim Demaille <akim@epita.fr>, and Alexandre Duret-Lutz <adl@gnu.org>. =cut 1; ### Setup "GNU" style for perl-mode and cperl-mode. ## Local Variables: ## perl-indent-level: 2 ## perl-continued-statement-offset: 2 ## perl-continued-brace-offset: 0 ## perl-brace-offset: 0 ## perl-brace-imaginary-offset: 0 ## perl-label-offset: -2 ## cperl-indent-level: 2 ## cperl-brace-offset: 0 ## cperl-continued-brace-offset: 0 ## cperl-label-offset: -2 ## cperl-extra-newline-before-brace: t ## cperl-merge-trailing-else: nil ## cperl-continued-statement-offset: 2 ## End: