NAME

       term::receive::bind - Keyboard dispatch from terminals

SYNOPSIS

       package require Tcl  8.4

       package require term::receive::bind  ?0.1?

       term::receive::bind object ?map?

       object map str cmd

       object default cmd

       object listen ?chan?

       object unlisten ?chan?

       object reset

       object next char

       object process str

       object eof

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DESCRIPTION

       This  package  provides  a  class  for  the  creation of simple dispatchers from character
       sequences to actions. Internally each dispatcher is  in  essence  a  deterministic  finite
       automaton with tree structure.

CLASS API

       The  package  exports  a  single  command,  the  class  command,  enabling the creation of
       dispatcher instances. Its API is:

       term::receive::bind object ?map?
              This command creates a new dispatcher object with the name object, initializes  it,
              and returns the fully qualified name of the object command as its result.

              The  argument is a dictionary mapping from strings, i.e. character sequences to the
              command prefices to invoke when the sequence is found in the input stream.

OBJECT API

       The objects created by the class command provide the methods listed below:

       object map str cmd
              This method adds an additional mapping from the string str to the action  cmd.  The
              mapping will take effect immediately should the processor be in a prefix of str, or
              at the next reset operation. The action is a command prefix  and  will  be  invoked
              with one argument appended to it, the character sequence causing the invokation. It
              is executed in the global namespace.

       object default cmd
              This method defines a default action cmd which will be invoked whenever an  unknown
              character sequence is encountered. The command prefix is handled in the same as the
              regular action defined via method map.

       object listen ?chan?
              This methods sets up a filevent listener for  the  channel  with  handle  chan  and
              invokes  the  dispatcher  object whenever characters have been received, or EOF was
              reached.

              If not specified chan defaults to stdin.

       object unlisten ?chan?
              This methods removes the filevent listener for the channel with handle chan.

              If not specified chan defaults to stdin.

       object reset
              This method resets the character processor to the beginning of the tree.

       object next char
              This method causes the character processor to process the  character  c.  This  may
              simply  advance the internal state, or invoke an associated action for a recognized
              sequence.

       object process str
              This method causes the character processor to process the character  sequence  str,
              advancing  the  internal state and invoking action as necessary. This is a callback
              for listen.

       object eof
              This method causes the character processor to handle EOF  on  the  input.  This  is
              currently no-op.  This is a callback for listen.

NOTES

       The  simplicity of the DFA means that it is not possible to recognize a character sequence
       with has a another recognized character sequence as its prefix.

       In other words, the set of recognized strings has to form a prefix code.

BUGS, IDEAS, FEEDBACK

       This document, and the package it describes,  will  undoubtedly  contain  bugs  and  other
       problems.    Please   report   such   in   the   category  term  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

       character input, control, dispatcher, listener, receiver, terminal

CATEGORY

       Terminal control

COPYRIGHT

       Copyright (c) 2006 Andreas Kupries <andreas_kupries@users.sourceforge.net>