[squeak-dev] The Trunk: Collections-nice.136.mcz

Nicolas Cellier uploaded a new version of Collections to project The Trunk:
http://source.squeak.org/trunk/Collections-nice.136.mcz

==================== Summary ====================

Name: Collections-nice.136
Author: nice
Time: 25 September 2009, 8:28:33 am
UUID: 814571f9-fe2a-4547-ae41-f0733a647794
Ancestors: Collections-nice.135

Fix from http://bugs.squeak.org/view.php?id=7095

RATIONALE:

Dictionary>>#collect: should preserve the keys

1) This is the ANSI specification
2) This is very logical

A Dictionary is a Bag of values indexed by unique, arbitrary keys.

OLD BEHAVIOUR CRITIC:

The old behaviour consisting in returning an OrderedCollection is wrong, at least for these reasons:
a Dictionary is unordered, and there is no reason to reassign keys (1 to: self size) with a random order...

BACKWARD COMPATIBILITY ISSUE:

Those relying on old behaviour should replace their code with something like:
        aDictionary values asOrderedCollection collect: aBlock.
or:
        (OrderedCollection newFrom: aDictionary) collect: aBlock.

=============== Diff against Collections-nice.135 ===============

Item was added:
+ ----- Method: Dictionary class>>newFromPairs: (in category 'instance creation') -----
+ newFromPairs: anArray
+
+ "Answer an instance of me associating (anArray at:i) to (anArray at: i+i)
+ for each odd i.  anArray must have an even number of entries."
+
+ | newDictionary |
+
+ newDictionary := self new: (anArray size/2).
+ 1 to: (anArray size-1) by: 2 do: [ :i|
+ newDictionary at: (anArray at: i) put: (anArray at: i+1).
+ ].
+ ^ newDictionary
+
+ "  Dictionary newFromPairs: {'Red' . Color red . 'Blue' . Color blue . 'Green' . Color green}. "!

Item was changed:
  ----- Method: Dictionary>>collect: (in category 'enumerating') -----
  collect: aBlock
  "Evaluate aBlock with each of my values as the argument.  Collect the
  resulting values into a collection that is like me. Answer with the new
  collection."
  | newCollection |
+ newCollection := self species new.
+ self associationsDo:[:each |
+ newCollection at: each key put: (aBlock value: each value).
+ ].
+ ^newCollection!
- newCollection := OrderedCollection new: self size.
- self do: [:each | newCollection add: (aBlock value: each)].
- ^ newCollection!