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Struct template unexpr

boost::proto::unexpr — Lets you inherit the interface of an expression while hiding from Proto the fact that the type is a Proto expression.


// In header: <boost/proto/expr.hpp>

template<typename Expr> 
struct unexpr :  Expr {
  // construct/copy/destruct
  unexpr(Expr const &);


For an expression type E, proto::is_expr<E>::value is true, but proto::is_expr<proto::unexpr<E> >::value is false.

unexpr public construct/copy/destruct

  1. unexpr(Expr const & expr);