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Struct empty_env

boost::proto::empty_env — The type of an object that represents a transform environment with no key/value pairs in it.


// In header: <boost/proto/transform/env.hpp>

struct empty_env {

  // public member functions
  proto::key_not_found operator[](unspecified) const;


empty_env public member functions

  1. proto::key_not_found operator[](unspecified) const;

    The type of the argument to this function has a user-defined implicit conversion from any type.