[plt-scheme] continuations problem

From: Alex Fritze (alex at croczilla.com)
Date: Tue Nov 15 11:22:33 EST 2005

Robby Findler wrote:

>This is a bug in drscheme. continuations jumping from the interactions
>window to the definitions window don't work right (the next interaction
>is always swallowed).
>
>The version in svn has been fixed.
>  
>
That's great!
Thanks,
Alex

>Robby
>
>At Tue, 15 Nov 2005 15:11:27 +0000, Alex Fritze wrote:
>  
>
>>Continuation novice question:
>>
>>Can someone explain to me the following behaviour?
>>
>>(define global-exit #f)
>>(call/cc (lambda (c) (set! global-exit c)))
>>(define a #f)
>>(define (foo)
>>  (print 1)
>>  (call/cc
>>    (lambda (return)
>>      (set! a return)
>>      (print 2)
>>      (global-exit)))
>>  (print 3))
>>-------------------------------------------------
>>Welcome to DrScheme, version 299.400p1.
>> > (foo)
>>12
>> > (a)
>> > (a)
>>3
>>
>>The first evaluation of (a) yields nothing. The second (and any 
>>subsequent ones) yield '3' as I would have expected...
>>
>>Thanks for any hints,
>>Alex
>>    
>>



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