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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.

-t