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Struct _data

boost::proto::_data — A PrimitiveTransform that returns the current data unmodified. If the data (third) parameter is a transform environment, it returns the value associated with the proto::data_type key. Otherwise, it returns the data parameter unmodified.

Synopsis

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


struct _data :  proto::transform<  {
  // member classes/structs/unions
  template<typename Expr, typename State, typename Data> 
  struct impl :  
    proto::is_env<proto::_env_var<proto::data_type>,
      proto::_env
    >::
  {
  };
};

Description

If the data (third) parameter is a transform environment, it returns the value associated with the proto::data_type key. Otherwise, it returns the data parameter unmodified.

Example:

proto::terminal<proto::data = 


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