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From: brangdon@cix.co.uk (Dave Harris)
Newsgroups: comp.std.c++
Subject: Re: Typeof considered harmful (long)
Date: Tue, 13 Nov 2001 00:56:18 GMT
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brianjparker@ozemail.com.au (Brian Parker) wrote (abridged):
> A solution, then is to specify that after function argument
> deduction, if function template parameters remain non-deduced and
> are not used as part of the function signature (excluding
> the return type), then the type is deduced to be that of the 
> initializing expression (or more accurately, it is deduced by the
> same algorithm that a function parameter is deduced to match
> an initialising function argument).

Interesting idea.

What happens with recursive loops?

    export template <typename R, typename P1>
    R func2( P1 p1 );
    
    export template <typename R, typename P1>
    R func1( P1 p1 ) {
        return func2( p1 );
    }

    export template <typename R, typename P1>
    R func2( P1 p1 ) {
        return func1( p1 );
    }

What is the type of func1(1)? Is the compiler required to give a 
diagnostic? If so, when?

What happens with "export"? The standard says in $14.8:

   [Note: an implementation may require that a translation unit
   containing the definition of an exported template be compiled
   before any translation unit containing an instantiation of
   that template.]

When is the definition of func1() complete? May the compiler require to 
see the definition of func2() before func1() can be instantiated?

  Dave Harris, Nottingham, UK | "Weave a circle round him thrice,
      brangdon@cix.co.uk      |   And close your eyes with holy dread,
                              |  For he on honey dew hath fed
 http://www.bhresearch.co.uk/ |   And drunk the milk of Paradise."

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