[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Fundamental design flaws
> From: "Anton van Straaten" <anton@xxxxxxxxxxxxxxxx>
> Tom Lord wrote:
> > I'm saying: either don't try to operate on the Scheme types at all, or
> > design 44 in such a way that the collections procedures work on (at
> > least):
> > ordinary lists as sequences (with any equivalence predicate)
> > ordinary lists as sets (with any equivalence predicate)
> > ordinary lists as ordered sequences
> > (with any equivalence /ordering predicate)
> > ordinary associative lists as dictionaries (with any
> > equivalence predicate)
> > (and probably other things I'm forgetting.)
> Some adapters which take a Scheme type and return a collection
> could do this, presumably within the bounds of the current 44
> spec, although I haven't tried to prove that to myself. Would
> that approach satisfy you, or do you think that the collection
> procedures should be able to operate directly on "unwrapped"
> Scheme types?
I realize that "Scheme style" tends to favor abstraction to a greater
degree than traditional lisp but I don't think that traditional lisp
style should be quite so neglected.
I'd be satisfied with, for example, a sequences and dictionaries
pacakge that works on nothing but "wrapped types" (e.g., not directly
on lists or vectors).
I'd _prefer_ one that where both sequences and dictionaries could be
ordinary association lists.
The only obstacle I see to that is the idea in 44 that both sequences
and dictionaries are "collections" where operations on collections
need to discriminate between sequences and dictionaries.