[plt-scheme] 3.99: lazy + match ?

Once again the import thing bites us. There is something to be worked  
out and it is not even close to what Jacob did.


On May 26, 2008, at 1:09 AM, Eli Barzilay wrote:

> On May 26, Jon Rafkind wrote:
>> I am trying to use match and the lazy language together but they
>> don't seem to be cooperating. Should this work?
>
> No, not without some explicit efforts that integrate `match' into the
> lazy language.  The easy solution would be to do that by forcing the
> matched value, but a proper solution will force just the part that is
> needed for the match but not more.  [You can usually get such magic to
> happen by re-evaluating the library in the lazy language -- but
> `match' is big enough that it won't work in this case.]
>
>
>> #lang lazy
>> (require scheme/match)
>>
>> (define-struct f (x))
>>
>> (printf "test1 ~a\n"
>>         (match (make-f 1)
>>                ((struct f (x)) 'ok)))
>>
>>>
>> match: no matching clause for #<promise:temp4>
>>
>>  === context ===
>> /home/kazzmir/svn/plt/trunk/collects/scheme/match/patterns.ss:17:0:
>> match:error
>>
>> It works fine in #lang scheme. I'm running from svn, r9936( mzscheme
>> v3.99.0.25 ).
>
> -- 
>           ((lambda (x) (x x)) (lambda (x) (x x)))          Eli  
> Barzilay:
>                   http://www.barzilay.org/                 Maze is  
> Life!
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