Marcel Taeumel uploaded a new version of Collections to project The Trunk:
http://source.squeak.org/trunk/Collections-mt.687.mcz

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

Name: Collections-mt.687
Author: mt
Time: 12 April 2016, 11:26:12.382799 am
UUID: e2089a91-178b-ab42-8e57-a71bfb023e74
Ancestors: Collections-mt.686

Support flatten across nested collections and streams.

=============== Diff against Collections-mt.686 ===============

Item was changed:
  ----- Method: SequenceableCollection>>flatten (in category 'converting') -----
  flatten
  	"Similar to #concatenation but removes all nesting except for strings.
  Example: {3 .4 .{2 .4 .{'hi'} .'ho'}} flatten = {3 .4 .2 .4 .'hi' .'ho'}"
  
  	^ Array streamContents: [:stream |
  		self do: [:each |
+ 			((each isCollection and: [each isString not]) or: [each isStream])
- 			(each isCollection and: [each isString not])
  				ifFalse: [stream nextPut: each]
  				ifTrue: [stream nextPutAll: each flatten]]]!

Item was added:
+ ----- Method: Stream>>flatten (in category 'converting') -----
+ flatten
+ 
+ 	^ Generator on: [:g | 
+ 		[self atEnd] whileFalse: [
+ 			self next in: [:object |
+ 				((object isCollection and: [object isString not]) or: [object isStream])
+ 					ifFalse: [g yield: object]
+ 					ifTrue: [object flatten do: [:each | g yield: each]]]]]!

Item was added:
+ ----- Method: Stream>>flattened (in category 'converting') -----
+ flattened
+ 	"An alias for #flatten
+ 	This message's name is in line with messages like #sorted or #reversed
+ 	while #flatten's is in line with #reverse (as per ANSI, see comment there)"
+ 
+ 	^ self flatten!