On 08 Oct 2014, at 16:46, Jan Kur� <kurs@iam.unibe.ch> wrote:
Hi,
I need to extract a source code from a block closure and I found something strange:
[ :ctx | [ ctx atEnd ] ifTrue: [ ] ] .
[ :ctx | [ ctx atEnd ] whileTrue:[ ] ].
Print of the first line returns:
'[ :ctx | [ ctx atEnd ] ifTrue: [ ] ]'
Print of the second line returns:
'[ ctx atEnd ]'
And honestly, I have no idea why. This behaviour was observed in Pharo3 and Pharo4.
Is there a way how to get a consistent result, i.e. '[ :ctx | [ ctx atEnd ] whileTrue:[ ] ]' for a second line?
I think this is an example that exposes a bug that we still have in the source mapping� on Context, see
sourceNode
"Return the source node of the method or the block corresponding to the receiver"
^ (method sourceNodeForPC: self neighborPCWithCorrectMapping) enclosingMethodOrBlockNode
"Uncomment the following once the pc->AST mapping is fixed"
"^ (method sourceNodeForPC: (pc ifNil: [ self startpc ])) enclosingMethodOrBlockNode"
#neighborPCWithCorrectMapping returns the inner send, which is wrong� this method needs to be rethought.
Yes it should. But that's not easy with optimized loop messages like whileTrue: & co.
Ideally, the source mapping needs to be fixed because that's the reason this method exists in the first place.
Or else we accepts that "1 to: 1 do: [ :i | ^ thisContext sourceNode ]" returns a method node instead of a block node and use a different implementation.
Marcus