grammar::me_intro(n)     Grammar operations and usage     grammar::me_intro(n)



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NAME
       grammar::me_intro - Introduction to virtual machines for parsing token
       streams

DESCRIPTION
       This document is an introduction to and overview of the basic
       facilities for the parsing and/or matching of token streams. One
       possibility often used for the token domain are characters.

       The packages themselves all provide variants of one virtual machine,
       called a match engine (short ME), which has all the facilities needed
       for the matching and parsing of a stream, and which are either
       controlled directly, or are customized with a match program. The
       virtual machine is basically a pushdown automaton, with additional
       elements for backtracking and/or handling of semantic data and
       construction of abstract syntax trees (AST).

       Because of the high degree of similarity in the actual implementations
       of the aforementioned virtual machine and the data structures they
       receive and generate these common parts are specified in a separate
       document which will be referenced by the documentation for packages
       actually implementing it.

       The relevant documents are:

       grammar::me_vm
              Virtual machine specification.

       grammar::me_ast
              Specification of various representations used for abstract
              syntax trees.

       grammar::me::util
              Utility commands.

       grammar::me::tcl
              Singleton ME virtual machine implementation tied to Tcl for
              control flow and stacks. Hardwired for pull operation.
              Uninteruptible during processing.

       grammar::me::cpu
              Object-based ME virtual machine implementation with explicit
              control flow, and stacks, using bytecodes. Suspend/Resumable.
              Push/pull operation.

       grammar::me::cpu::core
              Core functionality for state manipulation and stepping used in
              the bytecode based implementation of ME virtual machines.

BUGS, IDEAS, FEEDBACK
       This document, and the package it describes, will undoubtedly contain
       bugs and other problems.  Please report such in the category grammar_me
       of the Tcllib SF Trackers
       [http://sourceforge.net/tracker/?group_id=12883].  Please also report
       any ideas for enhancements you may have for either package and/or
       documentation.

KEYWORDS
       CFG, CFL, LL(k), PEG, TPDL, context-free grammar, context-free
       languages, expression, grammar, matching, parsing, parsing expression
       grammar, push down automaton, recursive descent, top-down parsing
       languages, transducer, virtual machine

CATEGORY
       Grammars and finite automata

COPYRIGHT
       Copyright (c) 2005 Andreas Kupries <andreas_kupries@users.sourceforge.net>




grammar_me                            0.1                 grammar::me_intro(n)
