[Boost-users] Re: enable_if and constructors

From: David Abrahams (dave_at_[hidden])
Date: 2005-04-05 16:58:44

Angus Leeming <angus.leeming_at_[hidden]> writes:

> David Abrahams wrote:
>>>     // Only the specializations (below) of this template will compile.
>>>     template <int N>
>>>     static foo
>>>     set() { return invalid_value; }
>> 
>> Without a definition for invalid_value, this is invalid code, and on a
>> conforming compiler, compilation fails at the point it is parsed.
>
> Thanks again. g++ 3.3 appears to happy differentiate between "valid" and
> "invalid" enum values with the code below, 

Well *that* code is valid, unlike the code of your previous post.

> so allow me to rephrase my earlier question: which of the two
> techniques we've discussed would you use? 

I have no opinion.

> I assume that one has technical merits over the other?

I don't know; they're both pretty ugly ;-)

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com