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'\" Generated from file '/usr/obj/ports/tcllib-1.10/tcllib-1.10/modules/grammar_me/me_intro.man' by tcllib/doctools with format 'nroff'
'\" Copyright (c) 2005 Andreas Kupries <andreas_kupries@users.sourceforge.net>
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.TH "grammar::me_intro" n 0.1 grammar_me "Grammar operations and usage"
.BS
.SH NAME
grammar::me_intro \- Introduction to virtual machines for parsing token streams
.SH DESCRIPTION
This document is an introduction to and overview of the basic
facilities for the parsing and/or matching of \fItoken\fR
streams. One possibility often used for the token domain are
characters.
.PP
The packages themselves all provide variants of one
\fIvirtual machine\fR, called a \fImatch engine\fR (short
\fIME\fR), 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
(\fIAST\fR).
.PP
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.
.PP
The relevant documents are:
.PP
.TP
\fBgrammar::me_vm\fR
Virtual machine specification.
.TP
\fBgrammar::me_ast\fR
Specification of various representations used for abstract syntax
trees.
.TP
\fBgrammar::me::util\fR
Utility commands.
.TP
\fBgrammar::me::tcl\fR
Singleton ME virtual machine implementation tied to Tcl for control
flow and stacks. Hardwired for pull operation. Uninteruptible during
processing.
.TP
\fBgrammar::me::cpu\fR
Object-based ME virtual machine implementation with explicit control
flow, and stacks, using bytecodes. Suspend/Resumable. Push/pull
operation.
.TP
\fBgrammar::me::cpu::core\fR
Core functionality for state manipulation and stepping used in the
bytecode based implementation of ME virtual machines.
.PP
.PP
.SH "BUGS, IDEAS, FEEDBACK"
This document, and the package it describes, will undoubtedly contain
bugs and other problems.
Please report such in the category \fIgrammar_me\fR of the
\fITcllib SF Trackers\fR [http://sourceforge.net/tracker/?group_id=12883].
Please also report any ideas for enhancements you may have for either
package and/or documentation.
.SH 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
.SH COPYRIGHT
.nf
Copyright (c) 2005 Andreas Kupries <andreas_kupries@users.sourceforge.net>

.fi