Author :
Thomas de Grivel
Date :
2020-05-17 17:22:33
Hash :9f68abc6 Message :specify semantics are for all data
index.md
Language
Thomas de Grivel <thoxdg@gmail.com>
https://kmx.io/
2020-05-17
# Language
## Structure
### Three components
Any formal language usable with a model is composed of three things :
- A schema (or grammar)
- Semantics
- Data
### Schema
In model theory a schema allows you to define an ontology,
that is a definition of what can and cannot be expressed in your
language.
It is a set of rules which make any pattern part of the language or not.
The most used schemas for formal language definition are grammars.
The schema is a generalistic view of all the data that can be
expressed in the language.
It can be a relative process where parts of the structure of the
language are combined to form a more complex schema, e.g. a
grammar made of simpler rules.
### Semantics
Semantics tell you the meaning of the language. They describe
how to translate your language into another one.
This is a relative process : a semantic is from a language to another,
even if it is the same language acting as source and destination
language.
Semantics give meaning to your language which otherwise is just another
data model.
A number of programming languages also export the semantics of
lower-level constructs such as mathematical operations from the processor
or disk access from the kernel.
Semantics tells you how your language relates to other languages.
It is a connection to other languages.
### Data
Data is valid use of the language for reasons pertaining to its
semantics.
It is a direct application of the language schema.
Semantics are appliable to all data.
Data is a choice from the possibilities of the language schema
driven by the semantics of the language.
Each datum represents a single valid use of the language and can
be uniquely identified.