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Struct template if_else_

boost::proto::if_else_ — A metafunction for generating ternary conditional expression types, a grammar element for matching ternary conditional expressions, and a PrimitiveTransform that dispatches to the proto::pass_through<> transform.


template<typename T, typename U, typename V> 
struct if_else_ :  proto::transform< if_else_<T, U, V> > {
  // types
  typedef proto::expr< proto::tag::if_else_, proto::list3< T, U, V > > type;           
  typedef type                                                         proto_base_expr;
  template<typename Expr, typename State, typename Data> 
  struct impl :
     proto::pass_through<if_else_>::template impl<Expr, State, Data>