From: Matthew Heaney <matthew_heaney@acm.org>
Subject: Re: Ada or C++ acting 'correctly' here?
Date: 1999/02/27
Date: 1999-02-27T00:00:00+00:00 [thread overview]
Message-ID: <m3hfs82by3.fsf@mheaney.ni.net> (raw)
In-Reply-To: 7b8c7u$sj1@drn.newsguy.com
bill@mooner writes:
> compare these 2 little programs, do same thing, one in C++
> and one in Ada. The C++ program compiles Ok, but result is
> negative, the Ada program refused to compile:
...
> test_multi.adb:6:18: value not in range of type "Standard.Integer"
> test_multi.adb:6:18: static expression raises "Constraint_Error"
...
> Now. Which would you consider the correct language behaviour?
> (same machine, Pentium pro, Linux.
You may be comparing apples and oranges.
I you want to duplicate the C++, then use a modular type. Instantiate
Text_IO.Modular_IO on Interfaces.Unsigned_32, and then compare results.
(Print out the values in hex.)
The other thing you could try is to create a non-static value in the Ada
program, and then be sure to compare with overflow checks off (the
default in gnat). This would be closer to the C++ program.
The fact that the Ada code refuses to compile, you should regard as a
Good Thing, since it doesn't make any sense to try to print out an
unrepresentable value.
next prev parent reply other threads:[~1999-02-27 0:00 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
1999-02-27 0:00 Ada or C++ acting 'correctly' here? bill
1999-02-27 0:00 ` Matthew Heaney [this message]
1999-02-27 0:00 ` Gautier.DeMontmollin
1999-02-27 0:00 ` Claudius Proculus
1999-02-27 0:00 ` Biju Thomas
1999-02-28 0:00 ` robert_dewar
1999-02-28 0:00 ` Florian Weimer
1999-03-01 0:00 ` dewar
1999-02-27 0:00 ` Florian Weimer
[not found] ` <36e8e201.48455851@netnews.worldnet.att.net>
1999-03-18 0:00 ` bglbv
1999-02-27 0:00 ` Steve Doiel
1999-02-28 0:00 ` robert_dewar
1999-02-28 0:00 ` William McKenzie
1999-03-01 0:00 ` Hubert B. Keller
1999-03-01 0:00 ` fraser
1999-03-02 0:00 ` Willliam V
1999-03-02 0:00 ` Pascal Obry
1999-03-02 0:00 ` Gautier.DeMontmollin
1999-03-02 0:00 ` kvisko
1999-03-02 0:00 ` robert_dewar
1999-03-02 0:00 ` SpamSpamSpam
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