Re: Fwd: Re: [Patch] Remove workaround for copy_backward

[Douglas Gregor <gregod at cs dot rpi dot edu>]

On Sunday 28 September 2003 01:41 pm, Gabriel Dos Reis wrote:
> Here is my take on the template constructror issue.  It is out of
> question to add a dummy argument, because:
>  (1) it an ABI breaking -- I do not have a strong opinion here;
>  (2) it makes us potentially accept "invalid" constructs -- even though
>      it may a harmless one.  For some reasons, people tend to use/depend
>      on things we think harmless; I'm pretty sure we'll get questions
>      like: "why does not vector<> use by nth argument?".

Good point. We should use the allocator parameter instead, e.g.,

    template <class _InputIterator>
      list(_InputIterator __first, _InputIterator __last,
           typename __enable_if<const _Allocator&,
                  (!__is_integral<_InputIterator>::value)
                  >::_M_type __a = _Allocator());

The effective signature doesn't change, so it won't accept the invalid 
constructs. Still changes the ABI in the presence of inlining, but otherwise 
I can't see how these changes would affect the ABI. They'd make a mess of the 
Doxygen documentation, though: might have to work around that with some macro 
hackery.

	Doug