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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Haskell, anyone?
Date: Mon, 16 Nov 2015 09:33:27 +0100
Organization: cbb software GmbH
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Date: 2015-11-16T09:33:27+01:00
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On Sun, 15 Nov 2015 14:11:07 -0800 (PST), mockturtle wrote:

>    function add(X, Y: Integer) return Integer;
> 
> rather than
> 
>     add :: Integer -> Integer -> Integer
> 
> (Yes, I understand that this means that add is a function that maps an
> integer into a function that maps integers to integers... [confused? :-)]

Hmm, but that is not an equivalent of "add." In mathematical notation "add"
is:

   add : Integer x Integer -> Integer

a mapping of pairs (Integer, Integer) to Integer.

[ However, in Ada's terms nothing requires it to be a mapping. E.g. "add"
may have side effects so that "add" with same arguments would return
different values. Which is no mapping then. There is still no pure
functions in Ada 2012, right? ]

> and I guess that this is taken from the common mathematical notation of
> functions) I guess one gets used to it, nevertheless, it is not the most
> intuitive syntax in the world... :-)

Seems so, except that doubled colon, which normally has the meaning
"deduced" rather than "equal."

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de