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[comment {-*- tcl -*- doctools manpage}]
[manpage_begin term::receive::bind n 0.1]
[copyright {2006 Andreas Kupries <andreas_kupries@users.sourceforge.net>}]
[moddesc {Terminal control}]
[titledesc {Keyboard dispatch from terminals}]
[category {Terminal control}]
[require Tcl 8.4]
[require term::receive::bind [opt 0.1]]
[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.
[section {Class API}]
The package exports a single command, the
class command, enabling the creation of
dispatcher instances. Its API
is:
[list_begin definitions]
[call [cmd term::receive::bind] [arg object] [opt [arg map]]]
This command creates a new dispatcher object with the name
[arg object], initializes it, and returns the fully qualified name of
the object command as its result.
[para]
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.
[list_end]
[section {Object API}]
The objects created by the class command provide the methods listed
below:
[list_begin definitions]
[call [arg object] [method map] [arg str] [arg cmd]]
This method adds an additional mapping from the string [arg str] to
the action [arg cmd]. The mapping will take effect immediately
should the processor be in a prefix of [arg 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.
[call [arg object] [method default] [arg cmd]]
This method defines a default action [arg 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 [method map].
[call [arg object] [method listen] [opt [arg chan]]]
This methods sets up a filevent listener for the channel with handle
[arg chan] and invokes the dispatcher object whenever characters have
been received, or EOF was reached.
[para]
If not specified [arg chan] defaults to [const stdin].
[call [arg object] [method unlisten] [opt [arg chan]]]
This methods removes the filevent listener for the channel with handle
[arg chan].
[para]
If not specified [arg chan] defaults to [const stdin].
[call [arg object] [method reset]]
This method resets the character processor
to the beginning of the tree.
[call [arg object] [method next] [arg char]]
This method causes the character processor to process the character
[arg c]. This may simply advance the internal state, or invoke an
associated action for a recognized sequence.
[call [arg object] [method process] [arg str]]
This method causes the character processor to process the character
sequence [arg str], advancing the internal state and invoking action
as necessary. This is a callback for [method listen].
[call [arg object] [method eof]]
This method causes the character processor to handle EOF on the
input. This is currently no-op.
This is a callback for [method listen].
[list_end]
[section 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.
[para]
In other words, the set of recognized strings has to form a
[term {prefix code}].
[section {BUGS, IDEAS, FEEDBACK}]
This document, and the package it describes, will undoubtedly contain
bugs and other problems.
Please report such in the category [emph term] of the
[uri {http://sourceforge.net/tracker/?group_id=12883} {Tcllib SF Trackers}].
Please also report any ideas for enhancements you may have for either
package and/or documentation.
[keywords terminal control {character input}]
[keywords listener receiver dispatcher]
[manpage_end]
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