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grammar::fa::dacceptor(3tcl) Finite automaton operations and usage grammar::fa::dacceptor(3tcl) 





NAME


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






SYNOPSIS


package require Tcl 8.5 9


package require snit


package require struct::set


package require grammar::fa::dacceptor ?0.1.2?


::grammar::fa::dacceptor daName fa
    ?-any any?


daName option ?arg arg ...?


daName destroy


daName accept? symbols










DESCRIPTION


This package provides a class for acceptors constructed from
    deterministic 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:







  

  
Option and the args determine the exact behavior of the
      command. See section ACCEPTOR METHODS for more explanations.
    
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 acceptor 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:



  

  
Destroys the automaton, including its storage space and associated
      command.

  

  
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 output 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,
    transducer






CATEGORY


Grammars and finite automata






COPYRIGHT


Copyright (c) 2004 Andreas Kupries <andreas_kupries@users.sourceforge.net>








  

    0.1.2
    tcllib