"
COPYRIGHT (c) 1993 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.
"
"{ Package: 'stx:libbasic' }"
Set subclass:#IdentitySet
instanceVariableNames:''
classVariableNames:''
poolDictionaries:''
category:'Collections-Unordered'
!
!IdentitySet class methodsFor:'documentation'!
copyright
"
COPYRIGHT (c) 1993 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.
"
!
documentation
"
same as a Set but compares elements using ==
(i.e. they must be identical - not just equal in structure).
Since compare is on identity (using ==), hashing is also done via
#identityHash instead of #hash.
[author:]
Claus Gittinger
"
! !
!IdentitySet methodsFor:'Compatibility-Squeak'!
copyWithout:anElement
"return a new collection consisting of a copy of the receiver, with
ALL elements equal to elementToSkip are left out.
No error is reported, if elementToSkip is not in the collection."
^ self select:[:each | each ~~ anElement]
"
#(1 2 3 4 5 6 7) asSet copyWithout:5
"
!
copyWithoutAll:aCollection
^ self select:[:each | (aCollection includesIdentical:each)]
"
#(1 2 3 4 5 6 7) asSet copyWithoutAll:#(3 5 7 9)
"
! !
!IdentitySet methodsFor:'adding & removing'!
removeIdentical:anObject ifAbsent:exceptionBlock
^ super remove:anObject ifAbsent:exceptionBlock
! !
!IdentitySet methodsFor:'private'!
find:key ifAbsent:aBlock
"Look for the key in the receiver. If it is found, return
the index of the slot containing the key, otherwise
return the value of evaluating aBlock.
Redefined to compare for identity instead of equality"
|index "{ Class:SmallInteger }"
length "{ Class:SmallInteger }"
startIndex probe |
length := keyArray basicSize.
"/
"/ length < 10 ifTrue:[
"/ "assuming, that for small sets the overhead of hashing
"/ is large ..."
"/ ^ keyArray identityIndexOf:key ifAbsent:aBlock.
"/ ].
"/
startIndex := index := self initialIndexForKey:key.
[true] whileTrue:[
probe := keyArray basicAt:index.
probe == key ifTrue:[^ index]. "<<<< == is different from inherited"
(self slotIsEmpty:probe) ifTrue:[^ aBlock value].
index == length ifTrue:[
index := 1
] ifFalse:[
index := index + 1
].
index == startIndex ifTrue:[
^ aBlock value
]
]
!
findKeyOrNil:key
"Look for the key in the receiver.
If it is found, return return the index of the first unused slot.
Grow the receiver, if key was not found, and no unused slots were present"
|index "{ Class:SmallInteger }"
length "{ Class:SmallInteger }"
startIndex probe
delIndex "{ Class:SmallInteger }" |
delIndex := 0.
length := keyArray basicSize.
startIndex := index := self initialIndexForKey:key.
[true] whileTrue:[
probe := keyArray basicAt:index.
key == probe ifTrue:[^ index].
(self slotIsEmpty:probe) ifTrue:[
delIndex == 0 ifTrue:[^ index].
keyArray basicAt:delIndex put:nil.
^ delIndex
].
probe == DeletedEntry ifTrue:[
delIndex == 0 ifTrue:[
delIndex := index
]
].
index == length ifTrue:[
index := 1
] ifFalse:[
index := index + 1
].
index == startIndex ifTrue:[
delIndex ~~ 0 ifTrue:[
keyArray basicAt:delIndex put:nil.
^ delIndex
].
^ self grow findKeyOrNil:key
].
]
"Modified: 26.3.1996 / 20:00:42 / cg"
!
hashFor:aKey
"return an initial index given a key."
^ aKey identityHash
"Created: 19.3.1997 / 15:18:59 / cg"
! !
!IdentitySet methodsFor:'testing'!
identicalContentsAs:aCollection
"return true if the receiver and aCollection represent collections
with identical contents (but not caring for order)."
aCollection size == self size ifFalse:[^ false].
^ aCollection conform:[:eachElement | (self includesIdentical:eachElement)].
"
|col|
col := #('aaa' 'bbb' 'ccc' 'ddd').
col identicalContentsAs:(col asIdentitySet).
col identicalContentsAs:(col copy asIdentitySet).
col identicalContentsAs:(col deepCopy asIdentitySet).
"
"Modified: / 13-10-2006 / 12:55:43 / cg"
!
includesIdentical:anObject
"for identitySet, the #includes: test already tests for identity"
^ self includes:anObject
"Created: / 11.12.1998 / 20:01:12 / cg"
! !
!IdentitySet class methodsFor:'documentation'!
version
^ '$Id: IdentitySet.st 10447 2009-06-14 13:09:55Z vranyj1 $'
! !