[plt-scheme] Multiple values

From: Bill Wood (william.wood3 at comcast.net)
Date: Tue Feb 21 02:32:21 EST 2006

On Tue, 2006-02-21 at 00:03 -0600, Robby Findler wrote:
   . . .
> Also, it my taste that a list should represent things where the number
> of elements varies. That is, I like to try to use cons and null when my
> function consumes/produces arbitrary values of this shape (in HtDP
> terms):
>   a list-of-X is either
>    - null
>    - (cons X list-of-X)
> instead of values where you know how many pairs there are going to be,
> always. In those cases, I find a struct works better (or, were I
> programming in ML, a tuple).

I tend to agree.  I have a convention of using improper lists when I
think "tuple", and leave proper lists for variable-length sequences.

So multiple-value are really only a little more than an efficiency hack
(as Lauri Alanko said)?

 -- Bill Wood

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