[R6RS] `call-with-current-continuation'

Michael Sperber sperber at informatik.uni-tuebingen.de
Sun Aug 20 06:28:07 EDT 2006

The current draft of Robby's semantics paper has this program:

(define k #f)
(define x 1)
(begin (call-with-current-continuation (lambda (k2) (set! k k2) 1))
       (set! x (+ x 1)))
(k 1)

In many Scheme systems, this program produces different results
depending on whether the `begin' is there or not, despite the R5RS
saying that it must not matter.

Generally, are we saying something somewhere about the continuations
of library-body expressions?  Shouldn't we?  I'm thinking that the
continuation should be delimited such that no subsequent library-body
expressions are in it.

I don't know what the continuation of `define' right-hand sides should
be, i.e. whether the variable would get re-assigned or re-bound or

Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla

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