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Function template is_in_range



// In header: <boost/log/expressions/predicates/is_in_range.hpp>

template<typename T, typename FallbackPolicyT, typename TagT, 
         template< typename > class ActorT, typename BoundaryT> 
  unspecified is_in_range(attribute_actor< T, FallbackPolicyT, TagT, ActorT > const & attr, 
                          BoundaryT const & least, BoundaryT const & most);


The function generates a terminal node in a template expression. The node will check if the attribute value is in the specified range. The range must be half-open, that is the predicate will be equivalent to least <= attr < most.