🚀 go-pugleaf

RetroBBS NetNews Server

Inspired by RockSolid Light RIP Retro Guy

Article View: comp.std.c++
Article #1989

Re: Pascal-like 'with' statement feasible in C++?

#1989
From: Kevin Lentin
Date: Mon, 18 Sep 1995 14:59
33 lines
2057 bytes
Eugene Radchenko (eugene@qsar.chem.msu.su) wrote:
>   type tpair = object
>          m,n: integer;
>          end;
>   var  pairs : array[1..10] of tpair;
> then you can write, for instance:
>   for i = 1 to 10 do
>     with pairs[i] do
>       m = n;
> instead of
>   for i = 1 to 10
>     pairs[i].m = pairs[i].n;
> I think the first version is clearer and probably more easily optimizable
> than the second.

Would make 0 difference to optimisers, I suspect. The first may look
shorter to you but it's still doing what the second one says. A compiler
would be able to recognise this in both cases.

With is purely a piece of syntactical sugar (with some ugly type problems
described elsewhere in this thread). It provides a way of making your life
easier (or different). Not the compiler.

-- 
[==================================================================]
[ Kevin Lentin                   |___/~\__/~\___/~~~~\__/~\__/~\_| ]
[ kevinl@cs.monash.edu.au        |___/~\/~\_____/~\______/~\/~\__| ]
[ Macintrash: 'Just say NO!'     |___/~\__/~\___/~~~~\____/~~\___| ]
[==================================================================]

[ comp.std.c++ is moderated.  Submission address: std-c++@ncar.ucar.edu.
  Contact address: std-c++-request@ncar.ucar.edu.  The moderation policy
  is summarized in http://dogbert.lbl.gov/~matt/std-c++/policy.html. ]
Technical Details
Message-ID: <43k1g3$klh@engnews2.Eng.Sun.COM>
Path: arc1-ca.pugleaf.net!engnews2.Eng.Sun.COM!taumet!clamage
References: <MATT.95Sep14102849@physics10.Berkeley.EDU>

Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!engnews2.Eng.Sun.COM!taumet!clamage
From: kevinl@fangorn.cs.monash.edu.au (Kevin Lentin)
Newsgroups: comp.std.c++
Subject: Re: Pascal-like 'with' statement feasible in C++?
Date: 18 Sep 1995 14:59:15 GMT
Organization: Monash University
Approved: clamage@eng.sun.com (comp.std.c++)
Distribution: world
Message-ID: <43k1g3$klh@engnews2.Eng.Sun.COM>
References: <MATT.95Sep14102849@physics10.Berkeley.EDU>
NNTP-Posting-Host: taumet.eng.sun.com
Content-Type: text
X-Nntp-Posting-User: kevinl
X-Newsreader: TIN [UNIX 1.3 950823BETA PL0]
X-Nntp-Posting-Host: fangorn.cs.monash.edu.au
Content-Length: 1142
X-Lines: 29
Originator: clamage@taumet