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Re: Fundamental design flaws

This page is part of the web mail archives of SRFI 44 from before July 7th, 2015. The new archives for SRFI 44 contain all messages, not just those from before July 7th, 2015.

    > 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.