From: John English <je@bton.ac.uk>
Subject: Re: Wanted: Ada STL. Reward: Ada's Future
Date: 1999/02/03
Date: 1999-02-03T00:00:00+00:00 [thread overview]
Message-ID: <36B856E4.D921C1D@bton.ac.uk> (raw)
In-Reply-To: Pine.BSF.4.05.9902020951180.15761-100000@shell5.ba.best.com
Brian Rogoff wrote:
> On Mon, 1 Feb 1999, Ehud Lamm wrote:
> > It seems that one problem in implementing STL in Ada95 is the lack of
> > pointer arithmetic. This causes perofremance problems in real sense (to
> > be exact the result is worse from a complexity point of view).
>
> I don't know what you mean here. Could you explain, or provide a pointer? :-)
IMHO performance is not the problem for implementing the STL in Ada.
For STL, a nice consequence of the pointer semantics in C and C++ is
that for a collection of N items, there are N+1 points where you can
insert a new item, and C/C++ pointer semantics lets you refer to the
position past the end of an array. This means that you have a way of
referring to the "extra" position by using a "beyond the end" pointer
in an array. The STL uses ranges [i,j) which cover the range from the
iterator i up to but not including the position j. This works just
as well for arrays as it does for vectors or maps or whatever.
In Ada this isn't possible -- e.g. type Foo is array(Boolean) of Bar
has no "beyond the end" index that can be used to form non-inclusive
ranges [i,j). This makes it hard to support arrays as "just another
collection type" in the way that the STL does, so you can't easily
define algorithms which can be applied impartially to arrays or
vectors or maps or whatever.
-----------------------------------------------------------------
John English | mailto:je@brighton.ac.uk
Senior Lecturer | http://www.it.bton.ac.uk/staff/je
Dept. of Computing | ** NON-PROFIT CD FOR CS STUDENTS **
University of Brighton | -- see http://burks.bton.ac.uk
-----------------------------------------------------------------
next prev parent reply other threads:[~1999-02-03 0:00 UTC|newest]
Thread overview: 102+ messages / expand[flat|nested] mbox.gz Atom feed top
1999-01-31 0:00 Wanted: Ada STL. Reward: Ada's Future Alexy V Khrabrov
1999-01-31 0:00 ` Simon Wright
1999-02-01 0:00 ` Stanley R. Allen
1999-02-01 0:00 ` dennison
1999-02-01 0:00 ` Jerry van Dijk
1999-02-01 0:00 ` Marin David Condic
1999-02-01 0:00 ` Matthew Heaney
1999-02-01 0:00 ` Alexy V Khrabrov
1999-02-01 0:00 ` Matthew Heaney
1999-02-01 0:00 ` Jeff Carter
1999-02-01 0:00 ` Brian Rogoff
1999-02-01 0:00 ` Ehud Lamm
1999-02-02 0:00 ` Richard D Riehle
1999-02-03 0:00 ` robert_dewar
1999-02-02 0:00 ` Pointer Arithmetic (was: Wanted: Ada STL....) adam
1999-02-02 0:00 ` William Clodius
1999-02-03 0:00 ` adam
1999-02-03 0:00 ` William Clodius
1999-02-03 0:00 ` Nick Roberts
1999-02-03 0:00 ` robert_dewar
1999-02-03 0:00 ` Jean-Pierre Rosen
1999-02-03 0:00 ` Nick Roberts
1999-02-03 0:00 ` robert_dewar
1999-02-03 0:00 ` Robert A Duff
1999-02-03 0:00 ` robert_dewar
1999-02-02 0:00 ` Wanted: Ada STL. Reward: Ada's Future Brian Rogoff
1999-02-02 0:00 ` robert_dewar
1999-02-04 0:00 ` Ehud Lamm
1999-02-03 0:00 ` John English [this message]
1999-02-03 0:00 ` Matthew Heaney
1999-02-03 0:00 ` Brian Rogoff
1999-02-04 0:00 ` Stephen Leake
1999-02-04 0:00 ` Brian Rogoff
1999-02-05 0:00 ` Stephen Leake
1999-02-05 0:00 ` Brian Rogoff
1999-02-04 0:00 ` Matthew Heaney
1999-02-04 0:00 ` Hyman Rosen
1999-02-05 0:00 ` Stephen Leake
1999-02-05 0:00 ` Hyman Rosen
1999-02-05 0:00 ` John English
1999-02-05 0:00 ` Brian Rogoff
1999-02-06 0:00 ` Matthew Heaney
1999-02-05 0:00 ` Tucker Taft
1999-02-05 0:00 ` Richard D Riehle
1999-02-05 0:00 ` Brian Rogoff
1999-02-05 0:00 ` Nick Roberts
1999-02-05 0:00 ` John English
1999-02-04 0:00 ` Ehud Lamm
1999-02-04 0:00 ` Brian Rogoff
1999-02-05 0:00 ` Matthew Heaney
1999-02-05 0:00 ` Brian Rogoff
1999-02-08 0:00 ` John English
1999-02-04 0:00 ` Pat Rogers
1999-02-04 0:00 ` Larry Kilgallen
1999-02-04 0:00 ` Pat Rogers
1999-02-04 0:00 ` Larry Kilgallen
1999-02-05 0:00 ` robert_dewar
1999-02-05 0:00 ` Tom Moran
1999-02-05 0:00 ` dewar
1999-02-05 0:00 ` Tom Moran
1999-02-05 0:00 ` dewar
1999-02-05 0:00 ` dennison
1999-02-06 0:00 ` dewar
1999-02-08 0:00 ` dennison
1999-02-08 0:00 ` robert_dewar
1999-02-08 0:00 ` dennison
1999-02-09 0:00 ` robert_dewar
1999-02-09 0:00 ` dennison
1999-02-09 0:00 ` Nick Roberts
1999-02-07 0:00 ` Simon Wright
1999-02-08 0:00 ` Corey Minyard
1999-02-08 0:00 ` Open Source Licensing (was: Wanted: Ada STL. Reward: Ada's Future) dennison
1999-02-08 0:00 ` Corey Minyard
1999-02-09 0:00 ` robert_dewar
1999-02-09 0:00 ` Corey Minyard
1999-02-09 0:00 ` dennison
1999-02-09 0:00 ` Corey Minyard
1999-02-09 0:00 ` Wanted: Ada STL. Reward: Ada's Future robert_dewar
1999-02-09 0:00 ` dennison
1999-02-10 0:00 ` robert_dewar
1999-02-07 0:00 ` Simon Wright
1999-02-05 0:00 ` Larry Kilgallen
[not found] ` <36ba730b.35540068@ <79fmg1$fn0$1@nnrp1.dejanews.com>
1999-02-06 0:00 ` Larry Kilgallen
1999-02-05 0:00 ` robert_dewar
1999-02-05 0:00 ` robert_dewar
1999-02-05 0:00 ` Larry Kilgallen
1999-02-05 0:00 ` robert_dewar
[not found] ` <79f24e$t14 <36BB4162.52FC6D9F@averstar.com>
1999-02-05 0:00 ` robert_dewar
1999-02-05 0:00 ` dennison
1999-02-05 0:00 ` Tucker Taft
1999-02-05 0:00 ` dennison
1999-02-05 0:00 ` robert_dewar
1999-02-05 0:00 ` dennison
1999-02-06 0:00 ` Nick Roberts
1999-02-04 0:00 ` Al Christians
1999-02-05 0:00 ` John English
1999-02-09 0:00 ` micro_ada
1999-02-05 0:00 ` Nick Roberts
1999-02-08 0:00 ` John English
1999-02-01 0:00 ` Jeff Carter
1999-02-08 0:00 ` Michael F Brenner
1999-02-05 0:00 ` Corey Minyard
replies disabled
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox