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From: marco@technoboredom.net (Marco Manfredini)
Newsgroups: comp.std.c++
Subject: Re: Proposal: two real uses for the "auto" keyword
Date: Mon, 26 Mar 2001 16:45:03 GMT
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gt5163b@prism.gatech.edu (Brian McNamara!) wrote in
<99l3nf$7n0$1@news-int.gatech.edu>: 


>Third: Is there a way to add cv-qualifiers or reference-ness?  In
>other words, can I do something like
>   auto const& tmp = (a+b)/(c-d);
>This would also be nice, as well as potentially more practical for
>some of the intended uses.  (There aren't any "implicit int"s left
>in the language trying to get in the way, are there?)

I think auto could be positioned as a placeholder for the right-hand 
type. Such that: 
{X}={Y}; 

can be rewritten as 

{X/auto=typeof(Y)}=Y;

In that case cv would come up quite naturally, like: 

const auto & tmp = (a+b)/(c-d); 

Anything else looks more complicated, since whatever type I declare on 
the lhs, it must be initializable with the rhs.

>
>I thought my 
>   Error<compile_time_bool,"User defined conditional error message">
>idea was good--but this one is even better!  If any compiler
>implementor adds both this extension and my user-defined error
>messages idea, I will be happy to purchase that compiler and quit
>using g++, even if I have to pay out the nose.  I am dying for these
>features! 
>

g++ already has typeof() and I think that auto can be hacked into it 
easily (for someone who is into the source).

-- 
Marco

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