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From: bekkah@web.de (Helium)
Newsgroups: comp.std.c++
Subject: Idea for calling multiple methods on a single object.
Date: Sun, 6 Jun 2004 23:54:22 +0000 (UTC)
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Xref: g2news1.google.com comp.std.c++:672

Multiple method-call:

At the moment calling more than one method on one object is
complicated. Imagine you want to call two methods on the (temporary)
result of a function. How dod you do this? One possibility is to call
the function twice.

foo ().method1 ();
foo ().method2 ();

This is a working solution, but calling the function twice could be
time consuming or even worse, the function could have some side
effects you only ant to appear once. So this isn't a solution.

Another possible solution is to store the rusult somewhere.

{
   Type tmp = foo ();
   tmp.method1 ();
   tmp.method2 ();
}


This is very unconvenient and the result has to be copied which cvan
be time consuming as well. And you have to know the function's return
type. If it's a reference to an object its type isn't know at
compile-time, so you have to use a reference, too. If it's a temporary
object you can't store it in a reference but you have to make a copy
of it. In both cases you have to create an additional temporary
(weither a reference or a complete object).



I suggest a new synthax to call multiple methods on a single object.
The notation I propose looks like this:

object.(method_1 (), method_2 (), ..., method_n ());
pointer->(method_1 (), method_2 (), ..., method_n ());


The result is that of the last function. This should feel familiar, as
a multiple method-call looks similar to calling several functions
using the operator ,:

(function_1 (), function_2 (), ..., function_n ());


This way the problem I showed above could easiely be solved like this:

foo ().(
   method1 (), 
   method2 ()
);

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