"
 COPYRIGHT (c) 1995 by Claus Gittinger
              All Rights Reserved

 This software is furnished under a license and may be used
 only in accordance with the terms of that license and with the
 inclusion of the above copyright notice.   This software may not
 be provided or otherwise made available to, or used by, any
 other person.  No title to or ownership of the software is
 hereby transferred.
"

'From Smalltalk/X, Version:2.10.5 on 26-mar-1995 at 4:21:12 am'!

Model subclass:#Plug
	 instanceVariableNames:'simulatedProtocol'
	 classVariableNames:''
	 poolDictionaries:''
	 category:'Kernel-Objects'
!

!Plug class methodsFor:'documentation'!

copyright
"
 COPYRIGHT (c) 1995 by Claus Gittinger
              All Rights Reserved

 This software is furnished under a license and may be used
 only in accordance with the terms of that license and with the
 inclusion of the above copyright notice.   This software may not
 be provided or otherwise made available to, or used by, any
 other person.  No title to or ownership of the software is
 hereby transferred.
"
!

version
"
$Header: /cvs/stx/stx/libview2/Plug.st,v 1.5 1995-08-29 17:44:29 claus Exp $
"
!

documentation
"
    A Plug is an objcet which simulates a protocol and evaluates
    a corresponding block when receiving messages.
    Its main use is for the demo doIts, to play the role of a model.
    Plugs are not used in the system and exist as a demo only.
    This class may be changed/removed/replaced without notice.
"
!

examples
"
    |plug|

    plug := Plug new.
    plug respondTo:#foo  with:[Transcript showCr:'received foo'].
    plug respondTo:#foo: with:[:arg | Transcript showCr:'received foo: ', arg printString].

    plug foo.
    plug foo:'some argument'
"
! !

!Plug class methodsFor:'instance creation'!

new
    ^ super basicNew privateInitialize
! !

!Plug methodsFor:'message sending'!

doesNotUnderstand:aMessage
    |block|

    block := simulatedProtocol at:aMessage selector ifAbsent:[].
    block isNil ifTrue:[
	^ super doesNotUnderstand:aMessage
    ].
    ^ block valueWithArguments:(aMessage arguments)
! !

!Plug methodsFor:'queries'!

respondsTo:aSelector
    (simulatedProtocol includesKey:aSelector) ifTrue:[^ true].
    ^ super respondsTo:aSelector
! !

!Plug methodsFor:'protocol definition'!

respondTo:aSelector with:aBlock
    simulatedProtocol at:aSelector put:aBlock
! !

!Plug methodsFor:'initialization'!

privateInitialize
    "this method is NOT called initialize to allow plugging that
     selector ..."

    simulatedProtocol := IdentityDictionary new.
! !