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From: Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: integers of 1, 2, 4 bytes
Date: Sun, 15 Jun 2014 15:09:59 -0700
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Date: 2014-06-15T15:09:59-07:00
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On 06/15/2014 10:57 AM, hreba wrote:
>
> My Ada book says that range checks are applied to constrained subtypes (like
> that one) but not to unconstrained subtypes, but but overflow checks are applied
> nevertheless. So I came up with
>
>    type Int16 is range -32768 .. 32767;
>    for Int16'Size use 16;
>    type INT is new Int16'Base;
>
> as a more efficient definition.

This is a (probably) failed attempt at premature optimization, and might not be 
what you want. Int is likely to be exactly the same as Int16; if it isn't, it's 
probably because Int16'Base is 32 bits.

So you should simply define the types you need in the most natural, readable way 
possible, and not worry about "efficiency" until such time as you are unable to 
meet your timing requirements. In Ada, "the most natural, readable way" usually 
means defining types based on the problem, not based on the predefined types 
that a compiler happens to implement.

-- 
Jeff Carter
"This trial is a travesty. It's a travesty of a mockery of a
sham of a mockery of a travesty of two mockeries of a sham. ...
Do you realize there's not a single homosexual on that jury?"
Bananas
27