On 18.07.2006, at 06:11, Chris Muller wrote:


What I personally don't like is that blocks in Squeak mix the static  
with the dynamic.

For methods, we have the static (dead) description of  a method:  
CompiledMethod.
When it is run, a MethodContext is allocated. For blocks, we only  
have the
dynamic structure: BlockContext, even for the static structure of "a  
Block".

This is much nicer done in Anthony's design of blocks for the  
ClosureCompiler.

      Marcus


> BlockContextStorage captures nargs, startpc, and home (a
> MethodContextStorage).  MethodContextStorage captures the 'method' (a
> CompiledMethodStorage).  CompiledMethodStorage captures 'header
> literals startPc endPc byteCodes sourcePointer className'.   
> Restoration
> works backward, first the CompiledMethod:
>
>   asCompiledMethod
> 	| answer |
> 	answer _
> 		CompiledMethod
> 			newMethod: endPc - startPc + 1 + 4
> 			header: header.
> 	literals withIndexDo:
> 		[ : each : index |
> 		answer
> 			literalAt: index
> 			put: each ].
> "	answer setSourcePointer: sourcePointer."  "<-- don't restore it, it
> could be wrong."
> "In fact..."
> sourcePointer > 0 ifTrue: [ answer zapSourcePointer ].
> 	answer
> 		replaceFrom: startPc
> 		to: endPc
> 		with: byteCodes
> 		startingAt: 1.
> 	self restoreLiterals: answer.
> 	^ answer
>
> then the MethodContext:
>
>   asMethodContext
> 	| cm |
> 	^ (MethodContext newForMethod: (cm _ method asCompiledMethod))
> 		privRefreshWith: cm ;
> 		yourself
>
> and, finally, the BlockContext:
>
>   asBlockContext
> 	| methodContext |
> 	methodContext _ home asMethodContext.
> 	^ (BlockContext newForMethod: methodContext method)
> 		home: methodContext
> 		startpc: startpc
> 		nargs: nargs
>
> Whew!  Sorry for this deluge, but if anyone has any suggestions for
> improving this I would be grateful.
>
>  - Chris
>
>
>
> --- Andreas Raab <andreas.raab at gmx.de> wrote:
>
>> Chris Muller wrote:
>>> Hi Noury, if you are in 3.7 or 3.8 you can use Magma to transfer a
>>> project containing Connected Morphs to another image.  Blocks and
>>> CompiledMethods are no problem.
>>
>> Out of curiosity, how does Magma deal with a situation where you
>> serialize a block referring to an iVar and the shape of that class
>> changes? Can you detect it?
>>
>> Cheers,
>>    - Andreas
>>
>>
>>
>
>