QuerySignal.st
author claus
Sat, 02 Sep 1995 18:08:30 +0200
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"
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 COPYRIGHT (c) 1995 by Claus Gittinger
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	      All Rights Reserved
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 This software is furnished under a license and may be used
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 only in accordance with the terms of that license and with the
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 inclusion of the above copyright notice.   This software may not
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 be provided or otherwise made available to, or used by, any
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 other person.  No title to or ownership of the software is
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 hereby transferred.
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Signal subclass:#QuerySignal
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	 instanceVariableNames:''
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	 classVariableNames:''
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	 poolDictionaries:''
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	 category:'Kernel-Exceptions'
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!
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!QuerySignal class methodsFor:'documentation'!
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copyright
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"
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 COPYRIGHT (c) 1995 by Claus Gittinger
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	      All Rights Reserved
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 This software is furnished under a license and may be used
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 only in accordance with the terms of that license and with the
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 inclusion of the above copyright notice.   This software may not
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 be provided or otherwise made available to, or used by, any
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 other person.  No title to or ownership of the software is
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 hereby transferred.
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!
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version
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$Header: /cvs/stx/stx/libbasic/QuerySignal.st,v 1.1 1995-09-02 16:08:30 claus Exp $
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!
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documentation
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"
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    QuerySignals are like signals, except that they are not accepted
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    by handlers for ordinary signals.
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    I.e. a signal handler for a normal signal will not handle a query
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    signal. Thus, these bypass any Object-ErrorSignal handler.
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! !
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!QuerySignal methodsFor:'queries'!
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isQuerySignal
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    ^ true
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!
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accepts:aSignal
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    "return true, if the receiver accepts the argument, aSignal.
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     (i.e. the receiver is aSignal or a parent of it). False otherwise."
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    |s|
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    aSignal isQuery ifFalse:[^ false].
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    s := aSignal.
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    [s notNil] whileTrue:[
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	self == s ifTrue:[^ true].
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	s := s parent
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    ].
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    ^ false
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! !