[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[ALAN: multiple return values]

Date: Sun, 29 Mar 87 02:29:12 EST
From: Alan Bawden <ALAN at AI.AI.MIT.EDU>
Re:   multiple return values

I will confine myself to reminding you of what I said the last time this
subject was raised:  Any implementation of multiple-values that doesn't
have the property that ordinary continuations (for example the continuation
passed to F in (+ (F) 3)) will accept and ignore extra values has missed
the point of multiple values.

Let me try putting it another way:  If you decide on a semantics for
multiple values that has the property that a correct implementation can be
written in straight R^3RS Scheme, then what have you accomplished?  You
haven't given the users anything they couldn't have written for themselves.
(Yes, perhaps you can arrange to implement it more efficiently, but since
when has that been the the spirit of the language?)