[plt-scheme] Multiple values

hufflen jean-michel wrote:
 >    Dear PLT Scheme friends,
 >
 >    I have a "philosophical" question.  If I write:
 >
 > (+ 0 (values 1 2))
 >
 > that causes an error, because "+" can consume only one value.  But 
why do you
 > raise the same error for:
 >
 > (define v (values 1 2))

Here v is a variable. In a variable definition

    (define x 42)

we declare that we want to use the name x for the value 42.

One variable names one value.

 >
 >    For my point of view, we should be able to write:
 >
 > (call-with-values (lambda ()
 >                     (let ((v (values 1 2)))
 >                       v))
 >   +)

Here you want v to be name for two values at once.
In stead one can do this:

 > (define-values (a b) (values 41 1))
 >  (+ a b)
42

 > (let-values ([(a b) (values 1 2)])
 >    (values a b))
1
2

-- 
Jens Axel Søgaard