Pop a list from beginning ? and memory saving...

[holger krekel]

Michael Chermside wrote:
> As for the original question (is it a good idea), I'd say YES, but with 
> one caveat. I think that it is important that the "iterable" utilities 
> operate on ANY iterator ... and that isn't possible with the intelligent 
> implementation of reverse. So I think that if iterable.reverse() were to 
> check the type of it's argument and use the clever approach (counting 
> backwards) for types list and tuple, but fall back on creating a temp 
> list and reversing it for other types, then that'd be quite useful. 
> Optimize the common case, but don't lose the universality.

i completly agree. Iterators in an iterators module should work 
with any iterator.  And reverse iterators are not really a brand 
new invention, as anyone using the C++-STL stuff knows. 

i-am-sure-lisp-always-had-it-ly y'rs, holger