Lutz - feature request

Started by Jeff, May 30, 2008, 06:56:57 AM

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Jeff

May 30, 2008, 06:56:57 AM Last Edit: December 31, 1969, 04:00:00 PM by Jeff
Lutz,



Can we have a built-in function to give us the type of a value?  Using cond with various predicates is *really* slow.  Then we can do nice things like building type-case macros.



Thanks,



Jeff
Jeff

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newBert

#1
May 30, 2008, 08:19:25 AM Last Edit: December 31, 1969, 04:00:00 PM by newBert
Does this simple function (without 'cond' and  predicates) would not be sufficient?


Code Select
(define (type x)
  ; returns the type of data
  (let (types '("boolean" "boolean" "integer" "float"
                "string" "symbol" "context"
                "primitive" "primitive" "primitive"
                "quote" "list" "lambda" "macro" "array"))
       (types (& 0xf ((dump x) 1)))))

I don't know any more where I found it...
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Jeff

#2
May 30, 2008, 10:04:04 AM Last Edit: December 31, 1969, 04:00:00 PM by Jeff
That works wonderfully.  Thank you!
Jeff

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Old programmers don\'t die. They just parse on...



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