Andreas Raab uploaded a new version of MorphicExtras to project The Trunk:
http://source.squeak.org/trunk/MorphicExtras-ar.72.mcz

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

Name: MorphicExtras-ar.72
Author: ar
Time: 23 January 2010, 2:50:05.444 pm
UUID: e8ecb63e-4699-974e-9af9-bb7b9a0c1e9c
Ancestors: MorphicExtras-dtl.71, MorphicExtras-nice.65

Merging MorphicExtras-nice.65:

Experimental: let a Rectangle merge in place (I called this swallow:)
This has two advantages:
- avoid repeated Object creation when we just want the gross result
- avoid closures writing to outer temps

IMHO, generalizing this kind of policy could have a measurable impact on GUI speed.
However, this is against current policy to never change a Point nor rectangle in place, so I let gurus judge if worth or not.


=============== Diff against MorphicExtras-dtl.71 ===============

Item was changed:
  ----- Method: BackgroundMorph>>subBounds (in category 'accessing') -----
  subBounds
  	"calculate the submorph bounds"
  
  	| subBounds |
+ 	subBounds := (submorphs ifEmpty: [^nil]) anyOne fullBounds copy.
+ 	self submorphsDo: 	[:m | subBounds swallow: m fullBounds].
- 	subBounds := nil.
- 	self submorphsDo: 
- 			[:m | 
- 			subBounds := subBounds isNil
- 						ifTrue: [m fullBounds]
- 						ifFalse: [subBounds merge: m fullBounds]].
  	^subBounds!