Levente Uzonyi uploaded a new version of Collections to project The Trunk:
http://source.squeak.org/trunk/Collections-ul.632.mcz==================== Summary ====================
Name: Collections-ul.632
Author: ul
Time: 5 May 2015, 1:10:58.584 am
UUID: 5581dccd-80b4-4a89-8918-450ff62093da
Ancestors: Collections-mt.631
Removed MutexForPicking and RandomForPicking from Collection along with the methods referencing them, because the accessor methods were private, and they were only intended to be used for shuffling.
Separated #groupBy: from #groupBy:having:.
=============== Diff against Collections-mt.631 ===============
Item was changed:
Object subclass: #Collection
instanceVariableNames: ''
+ classVariableNames: ''
- classVariableNames: 'MutexForPicking RandomForPicking'
poolDictionaries: ''
category: 'Collections-Abstract'!
!Collection commentStamp: '<historical>' prior: 0!
I am the abstract superclass of all classes that represent a group of elements.!
Item was changed:
----- Method: Collection class>>initialize (in category 'class initialization') -----
initialize
"Set up a Random number generator to be used by atRandom when the
user does not feel like creating his own Random generator."
- RandomForPicking := Random new.
- MutexForPicking := Semaphore forMutualExclusion.
Smalltalk addToStartUpList: self!
Item was removed:
- ----- Method: Collection class>>mutexForPicking (in category 'private') -----
- mutexForPicking
- ^ MutexForPicking!
Item was removed:
- ----- Method: Collection class>>randomForPicking (in category 'private') -----
- randomForPicking
-
- self deprecated: 'Use ThreadSafeRandom value instead. It''s not thread-safe to use this instance without the unaccessible MutexForPicking semaphore.'.
- ^ RandomForPicking!
Item was removed:
- ----- Method: Collection class>>startUp (in category 'system startup') -----
- startUp
- "Reseed the random generator at startup time such that a reloaded
- project will not repeat a previous pseudo-random sequence when
- selecting at random from a collection."
-
- MutexForPicking
- critical: [RandomForPicking initialize]!
Item was added:
+ ----- Method: Collection>>groupBy: (in category 'enumerating') -----
+ groupBy: keyBlock
+ "Like in SQL operation - Split the recievers contents into collections of elements for which keyBlock returns the same results, and return them."
+
+ | result |
+ result := Dictionary new.
+ self do: [ :each |
+ | key |
+ key := keyBlock value: each.
+ (result at: key ifAbsentPut: [ OrderedCollection new ])
+ add: each ].
+ ^result!
Item was changed:
----- Method: Collection>>groupBy:having: (in category 'enumerating') -----
groupBy: keyBlock having: selectBlock
"Like in SQL operation - Split the recievers contents into collections of elements for which keyBlock returns the same results, and return those collections allowed by selectBlock."
+
+ ^(self groupBy: keyBlock) select: selectBlock!
- | result |
- result := Dictionary new.
- self do:
- [ : each | | key |
- key := keyBlock value: each.
- (result
- at: key
- ifAbsentPut: [ OrderedCollection new ]) add: each ].
- ^ result select: selectBlock!
Locked
