|
Class: WeakValueIdentityDictionary
Object
|
+--Collection
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+--Set
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+--Dictionary
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+--IdentityDictionary
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+--WeakValueIdentityDictionary
- Package:
- stx:libbasic
- Category:
- Collections-Weak
- Version:
- rev:
1.8
date: 2019/02/10 13:42:30
- user: cg
- file: WeakValueIdentityDictionary.st directory: libbasic
- module: stx stc-classLibrary: libbasic
- Author:
- Claus (stolen from Stefans WeakValueDictionary)
WeakValueIdentityDictionaries behave like IdentityDictionaries,
as long as the values are still referenced by some
other (non-weak) object.
However, once the last non-weak reference ceases to exist,
the Dictionary will return nil for the value at position key.
(with some delay: it will be removed after the next garbage collect).
If you use this, be very careful since the collections size changes
'magically' - for example, testing for being nonEmpty and then
removing the first element may fail, since the element may vanish inbetween.
In general, never trust the value as returned by the size/isEmpty messages.
WeakArray
WeakIdentityDictionary
WeakIdentitySet
WeakValueDictionary
adding & removing
-
at: key put: anObject
-
add the argument anObject under key, aKey to the receiver.
Return anObject (sigh).
Redefined to block interrupts, to avoid trouble when dependencies
are added within interrupting high prio processes.
-
removeKey: aKey ifAbsent: aBlock
-
remove the association under aKey from the collection,
return the value previously stored there.
If it was not in the collection return the result
from evaluating aBlock.
Redefined to avoid synchronization problems, in case
of interrupts (otherwise, there could be some other operation
on the receiver done by another process, which garbles my contents).
-
removeValue: aKey ifAbsent: aBlock
-
remove the association under aValue from the collection,
return the key previously stored there.
If it was not in the collection return the result
from evaluating aBlock.
Redefined to avoid synchronization problems, in case
of interrupts (otherwise, there could be some other operation
on the receiver done by another process, which garbles my contents).
element disposal
-
update: something with: aParameter from: changedObject
-
an element (either key or value) died - clear out slots for
disposed keys.
private
-
valueContainerOfSize: n
-
return a container for values of size n.
use WeakArrays here.
queries
-
includes: anObject
-
redefined to block interrupts
(avoid change of the dictionary while accessing)
-
includesKey: key
-
redefined to block interrupts
(avoid change of the dictionary while accessing)
testing
-
isWeakCollection
-
return true, if the receiver has weak references to its elements.
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