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Re: [Scheme-reports] Write procedure is not backwards compatible

Marc Feeley scripsit:

> R7RS introduces a new output procedure called write-simple, which has
> the same semantics as the R5RS write procedure.  On the other hand,
> the R7RS write procedure handles shared structures differently than
> the R5RS.  For example :
>    (let ((x (list 1 2))) (write (list x x)))
>        displays ((1 2) (1 2)) in an R5RS system
>    and displays (#0=(1 2) #0#) in an R7RS system

R5RS leaves the output of `write` unspecified in such a case.  In actual
fact, it leaves the output of `(write (list 1 2))` unspecified as well.

I Hope, Sir, that we are not                    John Cowan
mutually Un-friended by this                    cowan@x
Difference which hath happened                  http://www.ccil.org/~cowan
betwixt us.     --Thomas Fuller, Appeal to Injured Innocence (1659)

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