[Chicken-janitors] #1002: define-values is overly restrictive

[Chicken Trac]

#1002: define-values is overly restrictive
-------------------------+--------------------------------------------------
 Reporter:  johnwcowan   |       Owner:         
     Type:  enhancement  |      Status:  new    
 Priority:  major        |   Milestone:  someday
Component:  unknown      |     Version:  4.8.x  
 Keywords:               |  
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 Currently, `define-values` requires that its lambda-list be a proper list
 of identifiers like `(a b)`, whereas it should allow `(a b . c)` and even
 `a`, which are both valid lambda-lists.

 The following definition achieves this:

 {{{
 (define-syntax define-values
    (syntax-rules ()
      ((define-values () exp)
       (call-with-values (lambda () exp) (lambda () 'unspecified)))
      ((define-values (var . vars) exp)
       (begin
         (define var (call-with-values (lambda () exp) list))
         (define-values vars (apply values (cdr var)))
         (define var (car var))))
      ((define-values var exp)
       (define var (call-with-values (lambda () exp) list)))))
 }}}

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Ticket URL: <http://bugs.call-cc.org/ticket/1002>
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