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Struct template exact

boost::proto::exact — For forcing exact matches of terminal types.


template<typename T> 
struct exact {


By default, matching terminals ignores references and cv-qualifiers. For instance, a terminal expression of type proto::terminal<int const &>::type will match the grammar proto::terminal<int>. If that is not desired, you can force an exact match with proto::terminal<proto::exact<int> >. This will only match integer terminals where the terminal is held by value.