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'From Smalltalk/X, Version:2.4.7 on 12-Jan-1993 at 21:32:36'!
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Dictionary subclass:#CacheDictionary
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instanceVariableNames:''
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classVariableNames:''
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poolDictionaries:''
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category:'Collections-Unordered'
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!
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CacheDictionary comment:'
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COPYRIGHT (c) 1993 by Claus Gittinger
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All Rights Reserved
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a CacheDictionary is a Dictionary which will not grow - i.e. keep
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only a limited number of elements.
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%W% %E%
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written jan 93 by claus
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'!
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!CacheDictionary methodsFor:'private'!
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findKeyOrNil:key
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"Look for the key in the receiver. If it is found, return
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the index of the association containing the key, otherwise
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return the index of the first unused slot. If no empty slot
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is available, make one empty"
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|index "{ Class:SmallInteger }"
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length "{ Class:SmallInteger }"
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startIndex
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probe|
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length := keyArray basicSize.
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startIndex := key hash \\ length + 1.
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index := startIndex.
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[true] whileTrue:[
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probe := keyArray basicAt:index.
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(probe == nil or: [probe = key]) ifTrue:[^ index].
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index := index + 1.
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index > length ifTrue:[
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index := 1.
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].
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index == startIndex ifTrue:[
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valueArray basicAt:startIndex put:nil.
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tally := tally - 1.
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^ startIndex
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].
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]
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! !
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