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

On 18/02/11 18:05, Dave Abrahams wrote:

On Fri, Feb 18, 2011 at 12:55 PM, Steven Watanabe wrote:

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AMDG

On 2/18/2011 9:50 AM, John Reid wrote:

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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.

Thanks.

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

Fair point.