I would like to know whether it's a design choice or a technical obstacle.

I've seen:

Parser>>assignment: varNode

" var ':=' expression => AssignmentNode."

| loc start |

(loc := varNode assignmentCheck: encoder at: prevMark + requestorOffset) >= 0

ifTrue: [^self notify: 'Cannot store into' at: loc].

        .....

TempVariableNode>>assignmentCheck: encoder at: location

^((self isBlockArg and: [Parser allowBlockArgumentAssignment not])

   or: [self isMethodArg])                                                                  "<-- not allowed !"

ifTrue: [location]

ifFalse: [-1]

But no explanation :(

Laurent

On Sun, Nov 28, 2010 at 10:59 AM, Max Leske <maxleske@gmail.com> wrote:

Yeah, that's true, I've noticed that too. I guess it's on purpose but I have no idea. AFAIK you can't assign a new value to a parameter anywhere in the method not only when using blocks. Maybe it's not possible because there is not really a 'variable' but only a reference. So assigning a new value to the parameter would effectively override the reference. But don't trust me on this....

Cheers,

Max

On 28.11.2010, at 10:54, laurent laffont wrote:

Sorry

foo: n 

  ^[:i| n := n+i. ]

vs

foo: n 
  |s| 
  s := n. 
  ^[:i| s := s+i. ]

Laurent

On Sun, Nov 28, 2010 at 10:51 AM, Max Leske <maxleske@gmail.com> wrote:

In the first example you didn't declare 's':

foo:n

^ [ :i || s | s:= s+i ]

Or did I misunderstand the question?

Cheers,

Max

On 28.11.2010, at 10:30, laurent laffont wrote:

Hi,

I can't write

foo: n 

  ^[:i| s := s+i. ]

but 

foo: n
  |s|
  s := n.
  ^[:i| s := s+i. ]

Why ?

Cheers, 

Laurent Laffont

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