1[comment {-*- tcl -*- doctools manpage}]
2[manpage_begin grammar::me_intro n 0.1]
3[copyright {2005 Andreas Kupries <andreas_kupries@users.sourceforge.net>}]
4[moddesc   {Grammar operations and usage}]
5[titledesc {Introduction to virtual machines for parsing token streams}]
6[category  {Grammars and finite automata}]
7[description]
8[keywords {virtual machine}]
9[keywords {push down automaton}]
10[keywords matching parsing transducer grammar expression]
11[keywords {context-free languages}     CFL  {context-free grammar}       CFG]
12[keywords {top-down parsing languages} TPDL {parsing expression grammar} PEG]
13[keywords {recursive descent} LL(k)]
14
15This document is an introduction to and overview of the basic
16facilities for the parsing and/or matching of [term token]
17streams. One possibility often used for the token domain are
18characters.
19
20[para]
21
22The packages themselves all provide variants of one
23
24[term {virtual machine}], called a [term {match engine}] (short
25
26[term ME]), which has all the facilities needed for the matching and
27parsing of a stream, and which are either controlled directly, or are
28customized with a match program. The virtual machine is basically a
29pushdown automaton, with additional elements for backtracking and/or
30handling of semantic data and construction of abstract syntax trees
31([term AST]).
32
33[para]
34
35Because of the high degree of similarity in the actual implementations
36of the aforementioned virtual machine and the data structures they
37receive and generate these common parts are specified in a separate
38document which will be referenced by the documentation for packages
39actually implementing it.
40
41[para]
42
43The relevant documents are:
44
45[para]
46[list_begin definitions]
47
48[def [package grammar::me_vm]]
49
50Virtual machine specification.
51
52[def [package grammar::me_ast]]
53
54Specification of various representations used for abstract syntax
55trees.
56
57[def [package grammar::me::util]]
58
59Utility commands.
60
61[def [package grammar::me::tcl]]
62
63Singleton ME virtual machine implementation tied to Tcl for control
64flow and stacks. Hardwired for pull operation. Uninteruptible during
65processing.
66
67[def [package grammar::me::cpu]]
68
69Object-based ME virtual machine implementation with explicit control
70flow, and stacks, using bytecodes. Suspend/Resumable. Push/pull
71operation.
72
73[def [package grammar::me::cpu::core]]
74
75Core functionality for state manipulation and stepping used in the
76bytecode based implementation of ME virtual machines.
77
78[list_end]
79[para]
80
81[section {BUGS, IDEAS, FEEDBACK}]
82
83This document, and the package it describes, will undoubtedly contain
84bugs and other problems.
85
86Please report such in the category [emph grammar_me] of the
87[uri {http://sourceforge.net/tracker/?group_id=12883} {Tcllib SF Trackers}].
88
89Please also report any ideas for enhancements you may have for either
90package and/or documentation.
91
92
93[manpage_end]
94