Re: Distinguish between procedure and macro

On Fri, 23 Mar 2007, Daniel Sadilek wrote:

> Hello,
> 
> is it possible to find out if an identifier is bound to an ordinary
> procedure or to a syntactic form?
> 
> My first guess was (type-of <identifier>) which raises an error if
> called with an identifier of a syntactic form. I tried to distinguish
> between procedure and syntactic form by catching that error:
> 
> (define-syntax syntactic-form?
>   (syntax-rules ()
>     ((_ identifier)
>      (with/fc
>       (lambda (error-record error-k)
>         #t)
>       (lambda ()
>         (type-of identifier)
>         #f)))))
> 
> But the error continuation doesn't get called.
> 

Not very nice, but this works:

(define-macro (procedure2? symbol)
  `(with-failure-continuation
    (lambda (error-record error-k)
      #f)
    (lambda ()
      (eval ',symbol))))



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