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Re: Testing availabilty of a procedure

Ingo Hohmann <ingo.hohmann@gmx.de> wrote:
> I try to test wether a procedure is defined, and define
> it if it isn't:
In guile you can use:

(if (not (defined? 'a))
    (define (a) #t))

For my own modules I have, however, defined defined? to be a special
form at it is in scm, which I used before guile. Which is more "standard"?
I have tried to keep my scripts compatible with scm, but such an essential
thing as (defined? 'a) and (defined? a) make them highly incompatible.
(Ok I have not checked the latest scheme report about this...) forgive
me if it is already standardized!

	Roland