[boost] Re: [boost.indirect container] RFC on interface changes

From: Thorsten Ottosen (nesotto_at_[hidden])
Date: 2005-02-09 14:27:47

"Jonathan Turkanis" <technews_at_[hidden]> wrote in message 
news:cub5f6$ulc$1_at_sea.gmane.org...
| Thorsten Ottosen wrote:

| > That is often a problem because of multiple overloads, that is,
| > we get ambiguity. Basically I think we got two alternatives:
| >
| > 1.
| > template< class Iter >
| > void container::assign( const iterator_range<Iter>& );
| > ...
| > container c;
| > c.assign( make_iterator_range( some_range ) );
| >
| > 2.
| >
| > template< class Range
| > void container::assign_range( const Range& ):
| > ....
| > container c;
| > c.assign_range( some_range );
| >
| > Which one do you prefer?
|
| I definitely prefer "assign" to "assign_range". Could you say more explcitly
| what the ambiguity would be if you try to make assign and insert to too much
| work?

yes, the problem shows up when an implicit conversion from Derived* to Base*
is needed and when another templated overload exists. The templated overload
does not require any conversions and so is deemed a better match.

The attached code shows the problem.

I guess the problem could be removed with disable_if<>.

-Thorsten

 

begin 666 range.cpp
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`
end