Re: [Boost-users] [tuple] Function object for nth element of a tuple

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I wanted something that would be a particular class, not a function object, for efficiency reasons. I don't follow you here. A polymorphic function object is a mere functor supporting result_of protocol. No efficiency penalty arise using them.

That's what I meant -- a function object (polymorphic or not), not a function template. -- Jeremiah Willcock