On Sun, 18 Jan 2015, commits at source.squeak.org wrote:

> Chris Muller uploaded a new version of Environments to project The Trunk:
> http://source.squeak.org/trunk/Environments-cmm.53.mcz
>
> ==================== Summary ====================
>
> Name: Environments-cmm.53
> Author: cmm
> Time: 16 January 2015, 2:54:24.767 pm
> UUID: 69b32fc7-98f1-4c19-9976-a38106a9ee63
> Ancestors: Environments-cmm.52
>
> - Only change key when it is NOT in the 'bindings' Dictionary, otherwise it would be in a state inconsistent with its new hash.
>
> =============== Diff against Environments-cmm.51 ===============
>
> Item was changed:
>  ----- Method: Environment>>renameClass:from:to: (in category 'classes and traits') -----
>  renameClass: aClass from: oldName to: newName
>  	"Rename the class, aClass, to have the title newName."
>
>  	| binding category |
>  	category := self organization categoryOfElement: oldName.
>  	self organization classify: newName under: category suppressIfDefault: true.
>  	self organization removeElement: oldName.
>
> + 	binding := self associationAt: oldName.
> - 	binding := self declarationOf: oldName.

The Dictionary API shouldn't be used from new code, especially not from 
the Environments code itself.
What was wrong with #declarationOf:? As I see the only difference is that 
it'll return nil instead of raising an error (#associationAt:). But that's 
not a problem, because the next line will raise an error anyway.

>  	declarations removeKey: oldName.
> + 	bindings removeKey: oldName.
> + "	self binding: binding removedFrom: self."
> - 	self binding: binding removedFrom: self.
>
> + 	binding key: newName.
> + 	declarations add: binding.
> + 	bindings add: binding.
> + "	self binding: binding addedTo: self."
> - 	binding := newName => aClass.
> - 	declarations add: binding.
> - 	self binding: binding addedTo: self.

I suspect that the removal of the #binding:removedFrom: and the 
#binding:addedTo: sends will break Environments, because another 
environment which imports this environment will not be notified about 
changes which happen here.
This problem is shadowed in case of Smalltalk - which imports itself - by 
the direct manipulation of the bindings dictionary.

Levente

>
>  	Smalltalk renamedClass: aClass from: oldName to: newName.
>  	SystemChangeNotifier uniqueInstance
>  		classRenamed: aClass
>  		from: oldName
>  		to: newName
>  		inCategory: category!
>
>
>