Re: [boost] [reference_wrapper] Overloading operator() inreference_wrapper

Subject: Re: [boost] [reference_wrapper] Overloading operator() inreference_wrapper
From: Peter Dimov (lists_at_[hidden])
Date: 2013-05-02 10:11:28

Kazutoshi Satoda wrote:
> The standard version has 4 member typedef which are conditionally
> defined: result_type, argument_type, first_argument_type,
> second_argument_type. If "to update boost::ref to match the standard
> version" includes addition of these members, it requires the argument
> type complete to determine the condition to (or not to) define these
> typedef. If you decide not to define these typedef based on the
> incompleteness, it will likely cause ODR violation.

Interesting. I've always considered these typedefs redundant, but this is 
the first time I see them as actively harmful.