1grammar::fa::dacceptorF(inn)ite automaton operations and ugsraagmemar::fa::dacceptor(n)
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NAME

8       grammar::fa::dacceptor - Create and use deterministic acceptors
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SYNOPSIS

11       package require Tcl  8.4
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13       package require snit
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15       package require struct::set
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17       package require grammar::fa::dacceptor  ?0.1.1?
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19       ::grammar::fa::dacceptor daName fa ?-any any?
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21       daName option ?arg arg ...?
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23       daName destroy
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25       daName accept? symbols
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DESCRIPTION

30       This  package provides a class for acceptors constructed from determin‐
31       istic finite automatons (DFA). Acceptors are objects which can be given
32       a string of symbols and tell if the DFA they are constructed from would
33       accept that string.  For the actual creation of the DFAs the  acceptors
34       are based on we have the packages grammar::fa and grammar::fa::op.
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API

37       The package exports the API described here.
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39       ::grammar::fa::dacceptor daName fa ?-any any?
40              Creates  a  new deterministic acceptor with an associated global
41              Tcl command whose name is daName. This command may  be  used  to
42              invoke  various operations on the acceptor. It has the following
43              general form:
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45              daName option ?arg arg ...?
46                     Option and the args determine the exact behavior  of  the
47                     command.  See  section ACCEPTOR METHODS for more explana‐
48                     tions.
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50                     The acceptor will be based on  the  deterministic  finite
51                     automaton stored in the object fa. It will keep a copy of
52                     the relevant data of the FA in its own storage, in a form
53                     easy  to  use  for  its  purposes.  This  also means that
54                     changes made to the fa after the construction of the  ac‐
55                     ceptor will not influence the acceptor.
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57                     If any has been specified, then the acceptor will convert
58                     all symbols in the input which are unknown to the base FA
59                     to that symbol before proceeding with the processing.
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ACCEPTOR METHODS

62       All acceptors provide the following methods for their manipulation:
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64       daName destroy
65              Destroys  the automaton, including its storage space and associ‐
66              ated command.
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68       daName accept? symbols
69              Takes the list of symbols and checks if the FA the  acceptor  is
70              based on would accept it. The result is a boolean value. True is
71              returned if the symbols are accepted, and False otherwise.  Note
72              that bogus symbols in the input are either translated to the any
73              symbol (if specified), or cause the acceptance  test  to  simply
74              fail.  No  errors  will  be thrown. The method will process only
75              just that prefix of the input which is enough to fully determine
76              (non-)acceptance.
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EXAMPLES

BUGS, IDEAS, FEEDBACK

80       This  document,  and the package it describes, will undoubtedly contain
81       bugs and other problems.  Please report such in the category grammar_fa
82       of  the Tcllib Trackers [http://core.tcl.tk/tcllib/reportlist].  Please
83       also report any ideas for enhancements you may have for either  package
84       and/or documentation.
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86       When proposing code changes, please provide unified diffs, i.e the out‐
87       put of diff -u.
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89       Note further that  attachments  are  strongly  preferred  over  inlined
90       patches.  Attachments  can  be  made  by  going to the Edit form of the
91       ticket immediately after its creation, and  then  using  the  left-most
92       button in the secondary navigation bar.
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KEYWORDS

95       acceptance,  acceptor,  automaton,  finite automaton, grammar, parsing,
96       regular expression, regular grammar, regular languages,  state,  trans‐
97       ducer
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CATEGORY

100       Grammars and finite automata
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103       Copyright (c) 2004 Andreas Kupries <andreas_kupries@users.sourceforge.net>
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108tcllib                               0.1.1           grammar::fa::dacceptor(n)
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