grammar::fa::dacceptoFinite)automaton operations agrammar::fa::dacceptor(3tcl)
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NAME
grammar::fa::dacceptor - Create and use deterministic acceptors
SYNOPSIS
package require Tcl 8.4
package require snit
package require struct::set
package require grammar::fa::dacceptor ?0.1.1?
::grammar::fa::dacceptor daName fa ?-any any?
daName option ?arg arg ...?
daName destroy
daName accept? symbols
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DESCRIPTION
This package provides a class for acceptors constructed from determin-
istic finite automatons (DFA). Acceptors are objects which can be given
a string of symbols and tell if the DFA they are constructed from would
accept that string. For the actual creation of the DFAs the acceptors
are based on we have the packages grammar::fa and grammar::fa::op.
API
The package exports the API described here.
::grammar::fa::dacceptor daName fa ?-any any?
Creates a new deterministic acceptor with an associated global
Tcl command whose name is daName. This command may be used to
invoke various operations on the acceptor. It has the following
general form:
daName option ?arg arg ...?
Option and the args determine the exact behavior of the
command. See section ACCEPTOR METHODS for more explana-
tions.
The acceptor will be based on the deterministic finite
automaton stored in the object fa. It will keep a copy of
the relevant data of the FA in its own storage, in a form
easy to use for its purposes. This also means that
changes made to the fa after the construction of the ac-
ceptor will not influence the acceptor.
If any has been specified, then the acceptor will convert
all symbols in the input which are unknown to the base FA
to that symbol before proceeding with the processing.
ACCEPTOR METHODS
All acceptors provide the following methods for their manipulation:
daName destroy
Destroys the automaton, including its storage space and associ-
ated command.
daName accept? symbols
Takes the list of symbols and checks if the FA the acceptor is
based on would accept it. The result is a boolean value. True is
returned if the symbols are accepted, and False otherwise. Note
that bogus symbols in the input are either translated to the any
symbol (if specified), or cause the acceptance test to simply
fail. No errors will be thrown. The method will process only
just that prefix of the input which is enough to fully determine
(non-)acceptance.
EXAMPLES
BUGS, IDEAS, FEEDBACK
This document, and the package it describes, will undoubtedly contain
bugs and other problems. Please report such in the category grammar_fa
of the Tcllib Trackers [http://core.tcl.tk/tcllib/reportlist]. Please
also report any ideas for enhancements you may have for either package
and/or documentation.
When proposing code changes, please provide unified diffs, i.e the out-
put of diff -u.
Note further that attachments are strongly preferred over inlined
patches. Attachments can be made by going to the Edit form of the
ticket immediately after its creation, and then using the left-most
button in the secondary navigation bar.
KEYWORDS
acceptance, acceptor, automaton, finite automaton, grammar, parsing,
regular expression, regular grammar, regular languages, state, trans-
ducer
CATEGORY
Grammars and finite automata
COPYRIGHT
Copyright (c) 2004 Andreas Kupries <andreas_kupries@users.sourceforge.net>
tcllib 0.1.1 grammar::fa::dacceptor(3tcl)