From: Martin Krischik <krischik@users.sourceforge.net>
Subject: Re: where exactly c++,c fail and Ada gets thru'
Date: Wed, 26 Apr 2006 19:32:50 +0200
Date: 2006-04-26T19:32:50+02:00 [thread overview]
Message-ID: <1235818.stAph9vF03@linux1.krischik.com> (raw)
In-Reply-To: e2o2ht$53$1@sunnews.cern.ch
Maciej Sobczak wrote:
> Yes, classes are used to define new types. Is there any problem with
> this? It is also necessary in Ada if we want to do just a bit more of
> what is provided by type and subtype constructs.
Say:
type Y_Type is range 1 .. 10;
subtype X_Type is new x range 1 .. 5;
function F (X: X_Type) return Y_Type is
begin
return X + 3;
end F
Now I would expect that an Ada compiler will not insert any runtime checks
as X + 3 is allways in the range of Y_Type. However:
function G (X: X_Type) return Y_Type is
begin
return X + 7;
end G;
may well be outside the range of Y_Type and if so CONSTRAINT_ERROR will be
raised.
Now say we have a suitable C++ range template:
typedef range<int, 1, 10> Y_Type;
typedef range<Y_Type, 1, 5> X_Type;
Y_Type F (X_Type X)
{
return X + 3;
}
Y_Type G (X_Type X)
{
return X + 7;
}
Now anyone up to the challenge to define:
template <typename Base_Type, Base_Type First, Base_Type Last>
range::operator = (Base_Type right)
template <typename Base_Type, Base_Type First, Base_Type Last>
range::operator + (Base_Type right)
template <typename Base_Type, Base_Type First, Base_Type Last>
range::range (Base_Type right)
in such a way that it works like Ada - inclusive the *realistic* change that
the compiler will optimize away the range check in F ().
Martin
--
mailto://krischik@users.sourceforge.net
Ada programming at: http://ada.krischik.com
next prev parent reply other threads:[~2006-04-26 17:32 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-04-24 4:19 where exactly c++,c fail and Ada gets thru' Ananth the Boss
2006-04-24 5:05 ` jimmaureenrogers
2006-04-24 7:45 ` Ananth the Boss
2006-04-24 19:17 ` Martin Krischik
2006-04-24 20:23 ` Simon Wright
2006-04-24 22:34 ` Keith Thompson
2006-04-24 22:33 ` Keith Thompson
2006-04-25 5:23 ` Jeffrey R. Carter
2006-04-26 17:48 ` Martin Krischik
2006-04-26 19:33 ` Keith Thompson
2006-04-26 15:10 ` Maciej Sobczak
2006-04-26 17:32 ` Martin Krischik [this message]
2006-04-27 10:07 ` Maciej Sobczak
2006-04-27 21:19 ` Keith Thompson
2006-04-28 7:00 ` Martin Krischik
2006-04-28 12:27 ` Maciej Sobczak
2006-04-29 7:03 ` Martin Krischik
2006-04-29 14:08 ` REH
2006-05-01 10:20 ` Xcriber51
2006-05-01 13:55 ` REH
2006-05-02 6:43 ` Maciej Sobczak
2006-04-27 16:48 ` REH
2006-04-28 7:49 ` Martin Krischik
2006-04-28 11:17 ` REH
2006-04-29 6:47 ` Martin Krischik
2006-04-24 8:13 ` Rod Chapman
2006-04-25 1:57 ` Steve
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