In message <01022215243600.04969@[...]..> , Vladimir Prus
<ghost@[...]..>  writes
> Kevlin Henney wrote:
> 
> >>At the moment lexical_cast<string>(whatever) will fail if 'whatever'
> decides
> >>to insert spaces in its representation. I think that it is not very
> >>convenient.
> 
> >You're right that it's not convenient, but I would hesitate to make
> >std::string a special case.
> 
> I really think that making std::string a special case is OK, because:
> 1. It will always be a special case, either inside lexical_cast or in user
> code.

I was referring to std::string as a special case of std::basic_string,
but that's something that can be accommodated without a problem, and
also to other string classes. However, in the latter case if the 'API'
is opened up, that offers a hook for extension.

> 3. Actually, string's operator>> has no choice but to stop when it encounters
> space, for it has no knowledge what was put in the stream.

Well, it does have a choice, but that's a historical design decision we
can't easily retake :-> 

> > A more general solution would be to replace the expression
> 
> > ... || !(interpreter >> result) || ...
> 
> > by
> 
> > ... || !interpret(interpreter, result) || ...
> 
> Yes, this is shurely better. What are chances that something like this will
> be added?

High :-) When I get a moment I will try to roll this change in with the
proposed floating point mods, plus tests and changes to docs.

Kevlin
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Kevlin Henney phone: +44 117 942 2990
Curbralan Limited mobile: +44 7801 073 508
mailto: kevlin@[...].. fax: +44 870 052 2289
 http://www.curbralan.com
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