[plt-scheme] Why does (begin ((lambda () (values))) (display "k")) fail?

--- Anders Conradi <beque at telia.com> wrote:

> Welcome to DrScheme, version 206p1.
> Language: Standard (R5RS).
>  > (define l (lambda () (values)))
>  > (begin (l) (display "k"))
> context expected 1 value, received 0 values
>  > ((lambda () (begin (l) (display "k"))))
> k

I can confirm this works in MzScheme but displays an
error in DrScheme (in the MzScheme language no less). 
It is due to the call to values with no value
supplied.  Some smaller examples:

> (values)

> (begin (values) 1)
context expected 1 value, received 0 values

> (display (values))
[bug icon] context expected 1 value, received 0 values

I can't explain it, but it only seems to occur when
the value of (values) is used in another expression.

Noel 


=====
Email: noelwelsh <at> yahoo <dot> com
Jabber: noelw <at> jabber <dot> org


	
		
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