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From: "G.B." <bauhaus@notmyhomepage.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Ada Annoyances
Date: Wed, 21 Jun 2017 22:40:18 +0200
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Xref: news.eternal-september.org comp.lang.ada:47050
Date: 2017-06-21T22:40:18+02:00
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On 21.06.17 16:52, pythoner6@gmail.com wrote:
> making the compiler work much harder to see that it can devirtualize the function calls

Not in Ada, like Dmitry explains; in fact, "devirtualization"
isn't really applicable to a language that requires explicit
notation for dynamic dispatch in the first place. What did
your example do?

The earlier proposals for Ada's STL had, e.g., (then) more efficient,
but less safe Cursor types whose objects would not know the structure
they were running along. Today, faster container operations are
available via checking control semantics, part of the language,
so if you are sure about what your algorithms are doing...

Another thing to consider is that, like in Python, a plain old
for loop might be a simple and fast solution if one can overcome
"functionist" fear for a moment, or focusing on both sides
of iteration control. (Demonstrably parallel loops are in the
making BTW.) A low level data structure like a plain old
built-in array can be at the heart of a (e.g. generic) subprogram
that iterates calling another subprogram (e.g. its generic actual)
with each of the array's components.

More involved recursive compile time resolution is unlikely to be
possible in Ada if its generics remain non-recursive.