[plt-scheme] The role of proper and improper lists?

From: Bill Wood (william.wood3 at comcast.net)
Date: Fri Jan 25 16:38:11 EST 2008

On Fri, 2008-01-25 at 19:18 +0000, Noel Welsh wrote:
> On Jan 25, 2008 6:34 PM, Bill Wood <william.wood3 at comcast.net> wrote:
> > I rather like having a tuple type (fixed-length heterogeneous sequence
> > ala SML or Python) distinct from proper lists.  When programming in lisp
> > or Scheme I sometimes use improper lists for tuples -- the difference in
> > structure acts as a reminder that the type is conceptually different.
> 
> I tend to use vectors in this case.  Now pattern-matching is more
> easily available (it's in 3.99's scheme language) vectors are less
> onerous to use.

That's a thought.  Indexing into a vector does correspond nicely (and
efficiently) with SML and Python.

 -- Bill Wood




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