Re: [Boost-users] challange to MPL gurus

Subject: Re: [Boost-users] challange to MPL gurus
From: Larry Evans (cppljevans_at_[hidden])
Date: 2011-12-12 18:31:24

On 12/12/11 17:04, Larry Evans wrote:
> On 12/12/11 16:39, Jeremiah Willcock wrote:
[snip]
> Looking at your code, it seems you solved the problem by removing
> the nested specialization of is_end, with a specialization in file
> scope of check_unless_end.  I've a vague memory of hearing some similar
> solution elsewhere.  Is there some reason why specializations cannot
> occur within the class?
> 
> -regards,
> Larry

The reason is explained in this thread:

http://groups.google.com/group/comp.lang.c++.moderated/browse_frm/thread/c040d6d750bf5c08/26bc1ce0b89b5979?#26bc1ce0b89b5979

and the workaround which Jeremiah showed is also found here:

http://stackoverflow.com/questions/2537716/why-is-partial-specialziation-of-a-nested-class-template-allowed-while-complete

after the phrase:

  You can work around this behavior by delegating the real work
  to another structure though:

HTH.

-regards,
Larry