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Date: Thu, 3 Jan 2019 01:30:19 -0800 (PST)
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Subject: Re: class wide iterable (and indexable)
From: George Shapovalov <gshapovalov@gmail.com>
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Xref: reader01.eternal-september.org comp.lang.ada:55172
Date: 2019-01-03T01:30:19-08:00
List-Id: <comp.lang.ada>

> ARM A.18.2(34.3)ff[1] has both forms.
Ah, thank you for the pointer. Unfortunately ARM is a rather heavy reading,=
 targeted more at language implementation (so, not the first place to look =
at if there are other sources). But I guess I enter this territory already =
while trying to reimplement indexing and iteration..

> You might be interested in Emmanuel's 'traits'-based containers, see
> [2], [3].
Thanks, I'll take a look.

> The Ada 95 Booch Components[4] follow this model. One reason they
> weren't taken as a model for Ada.Containers was that the model requires
> multiple levels of generic instantiation of child packages:
Yes, I am very well aware of that :) (and I used Booch components before, t=
his is also why surprise, as Ada.Containers seem to be rather inspired by t=
hem).
However here we have the trade-off of an extra few clear lines of code (mos=
t commonly one trivial would suffice I suspect) for the capability to do a =
more "universal" algorithm implementation. I'd say it is well worth it, but=
 apparently this was not the majority opinion..

Thanks again for all the pointers!
George