[plt-scheme] Lisp-style keyword parameters

From: Don Felgar (dfelgar at rainier-infosys.com)
Date: Sun Apr 20 20:05:27 EDT 2003

I'm converting some Guile code to PLT.  I've used extensively the
Guile let-keywords operator which implements Lisp-style optargs.  For

  (define (make-field name . args)
    (let-keywords args #f
        ((display-name name)
         (description #f)
         (required? #f)


  (make-field "foo" :required? #t)
  (make-field "bar" :description "description for bar" :required? #t)

and so forth.

The only thing at all comparable that I've been able to find for PLT
is in the Swindle package, but I don't understand the macros there,
and I can't find an example of Swindle keyword usage.

Ideally I'd like to find a let-keywords for PLT, or something very
close to it.  I'm using keywords mostly in class constructors (slib's
yasos currently), so if PLT classes have a similar mechanism, that
might fulfill the role also.


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