Q: With statement in C++ ?

Cristian Georgescu

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Sep 18, 1997, 3:00:00 AM9/18/97

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Q: With statement in C++ ?
================

Is there a way to mimic a with statement in c++:

Instead of:

a.b.c.action1();
a.b.c.action2();
a.b.c.action3();
a.b.c.action4();

Write:

with a.b.c {
.action1();
.action2();
.action3();
.action4();
}

--
Cristian Georgescu
_________________________________________________
Smith Industries
Aerospace & Defense Systems
7-9 Vreeland Road,
Florham Park, NJ 07932, USA.
_________________________________________________
E-mail: Georgescu...@si.com
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Ron Hunsinger

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Sep 18, 1997, 3:00:00 AM9/18/97

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In article <01bcc3e5$b2f10bc0$2031...@worldnet.worldnet.att.net>,
"Cristian Georgescu" <Cristian....@worldnet.att.net> wrote:

> Q: With statement in C++ ?
> ================
>
> Is there a way to mimic a with statement in c++:
>
> Instead of:
>
> a.b.c.action1();
> a.b.c.action2();
> a.b.c.action3();
> a.b.c.action4();
>
> Write:
>
> with a.b.c {
> .action1();
> .action2();
> .action3();
> .action4();
> }

Sure. Let T be the type of a.b.c. Then write:

{
T& t = a.b.c;
t.action1();
t.action2();
t.action3();
t.action4();
}

This should generate identical code to what the Pascal 'with' statement
generated (even if "a.b.c" was something more complicated that would have
prevented the C++ compiler from generating the same code anyway), is nearly
as terse as the Pascal source, and a lot less error-prone in the presence
of nested 'with's.

-Ron Hunsinger

Alan Griffiths

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Sep 19, 1997, 3:00:00 AM9/19/97

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In article: <01bcc3e5$b2f10bc0$2031...@worldnet.worldnet.att.net> "Cristian Georgescu" <Cristian....@worldnet.att.net> writes:
>
>
> Q: With statement in C++ ?
> ================
>
> Is there a way to mimic a with statement in c++:
>
> Instead of:
>
> a.b.c.action1();
> a.b.c.action2();
> a.b.c.action3();
> a.b.c.action4();
>
> Write:
>
> with a.b.c {
> .action1();
> .action2();
> .action3();
> .action4();
> }

Yes, let C::action[1-4] return *this...

a.b.c.action1()
.action2()
.action3()
.action4();

But I doubt that client code should access b or c anyway. :)

__
Alan Griffiths | Senior Systems Consultant, Experian (Formerly CCN)
alan.gr...@experian.com (agrif...@ma.ccngroup.com, Tel. +44 115 934 4517)
(ACCU C++ SIG organiser | <http://www.accu.org/> al...@octopull.demon.co.uk)

TytySoft

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Sep 19, 1997, 3:00:00 AM9/19/97

to

A: not really.

but take a look:

// --- "sample.cpp"

struct C
{
int action1(){ return 1; }
int action2(){ return 2; }
int action3(){ return 3; }
};

struct B
{
C c;
};

struct A
{
B b;
};

void f(void)
{
A a;
C& rc = a.b.c;

rc.action1(); // same as a.b.c.action1()
rc.action2(); // same as a.b.c.action2()
rc.action3(); // same as a.b.c.action3()
}

hope it helps,
Augustin MOGA (aka { t i T i } )

Cristian Georgescu wrote in article
<01bcc3e5$b2f10bc0$2031...@worldnet.worldnet.att.net>...

>Q: With statement in C++ ?
>================
>
>Is there a way to mimic a with statement in c++:
>
>Instead of:
>
>a.b.c.action1();
>a.b.c.action2();
>a.b.c.action3();
>a.b.c.action4();
>
>Write:
>
>with a.b.c {
> .action1();
> .action2();
> .action3();
> .action4();
>}
>
>

>--
>Cristian Georgescu
>_________________________________________________
> Smith Industries
> Aerospace & Defense Systems
> 7-9 Vreeland Road,
> Florham Park, NJ 07932, USA.
>_________________________________________________
>E-mail: Georgescu...@si.com

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