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From: "Corey Ashford" <yeroca@rocketmail.com>
Subject: Question for the folks who designed Ada95
Date: 1999/04/26
Message-ID: <7g2qu4$ca4$1@usenet.rational.com>#1/1
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Newsgroups: comp.lang.ada
Date: 1999-04-26T00:00:00+00:00
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About modular types.

In general, I think they are pretty good, but
there is one thing that has been brought up several
times on this newsgroup and I consider that the
solutions offered were less than adequate.

Shifts!

Why didn't Ada95 make a shift operator a first-class
operator on modular types.

There wouldn't be any need to introduce new syntax.
Something like this would be good:

type reg32 is mod 2**32;

...
x : reg32;
y : reg32;
z : natural;

...

x := reg32'shift_left(y, z);


The problem with the interfaces package shift
operators is that they have fixed types.  So it's
difficult to write code for types whose size can vary.

Any thoughts as to why the shift operator wasn't given
a better treatment?  Or am I all wet, and there's really a good way to do shifts?

(Please don't suggest using divides or multiplies as
the efficiency of the code generated can vary widely across different
compilers and optimization levels).


Thanks

- Corey