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From: blaak@infomatch.com (Ray Blaak)
Subject: Constants vs Functions (was Re: Optimizing recursion...)
Date: 1998/08/27
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eachus@spectre.mitre.org (Robert I. Eachus) writes:

>   I bring this up becuase it is one of those things that you normally
>don't think of in advance, but once you see it, you use it all over
>the place:
>   function Max_Name_Length return Positive;
>   ...
>   function Max_Name_Length return Positive is
>   begin return 120; end Max_Name_Length;
>may seem like a lot of extra work compared to:
>   Max_Name_Length: constant Positive := 120;
>but it limits the amount of code that may have to be changed.

This is a sound suggestion, but one problem with it is that such constants
tend to be used to define ranges, array sizes, etc. If it is not a constant
then the static property is lost, and things like compile-time fixed-sized
arrays, and constraint check elimination become difficult.

Cheers,                                        The Rhythm is around me,
                                               The Rhythm has control.
Ray Blaak                                      The Rhythm is inside me,
blaak@infomatch.com                            The Rhythm has my soul.