Re: [Boost-users] Determine at compile time whether type has subtraction semantics?

Subject: Re: [Boost-users] Determine at compile time whether type has subtraction semantics?
From: Dave Abrahams (dave_at_[hidden])
Date: 2011-02-18 13:05:20

On Fri, Feb 18, 2011 at 12:55 PM, Steven Watanabe <watanabesj_at_[hidden]> wrote:
> AMDG
>
> On 2/18/2011 9:50 AM, John Reid wrote:
>>
>> Is it possible to determine at compile-time if a type has subtraction
>> semantics? E.g. in struct A<T> I would like to decide at compile-time
>> not to execute &A::subtract in the register_fns method. Then the
>> subtract method is not instantiated and there is no error.
>
> I believe the type traits extensions in the
> review queue handle this.

Just to be clear, you can only check syntax at compile-time, not semantics.

-- 
Dave Abrahams
BoostPro Computing
http://www.boostpro.com