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From: Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups: comp.lang.ada
Subject: Re: project euler 26
Date: Fri, 08 Sep 2023 22:02:36 +0100
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"G.B." <bauhaus@notmyhomepage.invalid> writes:

> On 07.09.23 01:32, Ben Bacarisse wrote:
>
>
>> A fix (though it's not really ideal) would be to use function
>> composition here (inventing . as the composition operator):
>
> Hm. A stateful, composed function that needs to be applied
> in a certain way. Is that so different from  calling interface
> subprograms of a certain type?

There was nothing stateful (as I understand the term) in either function
being composed.

As to your question, not being an Ada expert I can't answer.  I could
not see any fix other than passing a composed function which would, it
seems, have to be written afresh.  Is that what your question refers to?
If so, then yes there is a small difference: writing a function (albeit
just a few lines) vs. applying an operator to two already written
functions.

> A wild guess: only "monads" would add substantial toppings
> to the commonalities. Considering the computational powers of
> C++'s "hair-raising template metaprogramming" [14.4], the idea
> of "Ada generics" = "functional style" is probably limited
> in scope.
>
> So, does type composition help?

My turn to guess now: you are not being serious?  I see no connection to
monads or type composition.  And why bring C++ into it?

Having found the maximum of the function 'Period' over a range 2..999,
you might find yourself a week later wanting the maximum absolute value
of the numbers in an Ordered_Map.  And then later the maximum of sine
squared over the elements of 2D array.  You might want to have a
resuable "maximum of F over X" function, so I was curious about how
close one could get to this in Ada (or, more accurately, what the
restrictions on X and F might have to be).

-- 
Ben.