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Software Details

Title: The Language Machine
Submitter: Peri Hankey
Description: I hope that readers of this list will be interested in the language machine
- a toolkit for language and grammar. This is available as free software
under Gnu GPL from

The software consists of a generalised grammatical engine and several
flavours of a metalanguage compiler. The grammatical engine applies
grammatical substitution rules that take the general form

sequence-to-be-matched <- sequence-to-be-substituted ;

where the sequences to be matched and substituted may be of any length, may
contain terminal, non-terminal and lexical class symbols, and may include
variable bindings and references, variable declarations and immediate or
deferred side-effect actions including calls on external procedures.

There is a summary of how all this relates to the received wisdom about
language implementation at:

The language machine can produce a diagram which shows exactly what happens
when unrestricted rewriting rules are applied to an input stream. This
diagram is explained with two very simple examples at:

The software is intended for practical applications, for research, and as a
way of explaining some fundamental mechanisms of language and grammar.

As far as I know, there is no other system which displays so clearly how
grammatical structure arises from the application of 'flat' rewriting rules.

Instructions for downloading and building the software can be found at the
website, where there are also pointers to a forum and related resources.

Peri Hankey
Linguistic Field(s): Computational Linguistics

LL Issue: 16.2629
Date Posted: 12-Sep-2005

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