Re: [Jscheme-user] question regarding dynamic function definition

[Ken A. <kan...@bb...>]

I'm not exactly sure what you want, but there are several ways to do this.

The first is to use a procedure that uses some JScheme internals:

(define (dynamicdefine name procedure)
  (jscheme.JS.setGlobalValue name procedure))

Example:
> (dynamicdefine "bar" (lambda (x) (+ x 3)))
#null
> (describe bar)
Closure named ??
(lambda (x) (+ x '3))

#t

A more appropriate way might be to use a macro:

(define-macro (dynamicdefine name procedure)
  `(set! ,(string->symbol name) ,procedure))

But this requires understanding quasiquote.  This macro expands like this:

> (macroexpand '(dynamicdefine "bar" (lambda (x) (+ x 3))))
(set! bar (lambda (x) (+ x 3)))

Why do you need such a factory?

At 02:03 PM 10/8/2004 -0400, Mark McGettrick wrote:
>Hey
>I'm new to JScheme however I've quickly discovered my need to do a relatively complex thing... I'd like to be able to pass a string into a function which will then act as a factory to create a new function who's name is equal to the value of the input string. In other words:
>
>foo is set equal to "bar"
>dynamicdefine (my function) with foo as a parameter should return a new function (whatever that may be) assigned to the name "bar"
>now there would be a new function called: bar
>
>I guess this all comes down to: is there a way to cause the value of a string to be used as the name of a new symbol?
>Perhaps I'm not even asking the question correctly...
>Help?
>
>Thanks,
>-mark
>
>
>
>-------------------------------------------------------
>This SF.net email is sponsored by: IT Product Guide on ITManagersJournal
>Use IT products in your business? Tell us what you think of them. Give us
>Your Opinions, Get Free ThinkGeek Gift Certificates! Click to find out more
>http://productguide.itmanagersjournal.com/guidepromo.tmpl
>_______________________________________________
>Jscheme-user mailing list
>Jsc...@li...
>https://lists.sourceforge.net/lists/listinfo/jscheme-user