CGAL::Output_rep< T, F > Class Template Reference

#include <CGAL/IO/io.h>

Inherits from

CGAL::IO_rep_is_not_specialized_aux< Dummy >.

Definition

template<class T, class F = ::CGAL::Null_tag>
class CGAL::Output_rep< T, F >

The purpose of Output_rep is to provide a way to control output formatting that works independently of the object's stream output operator.

If you don't specialize Output_rep for T, T's stream output operator is called from within Output_rep, by default. If you want another behavior for your type T, you have to provide a specialization for that type. Furthermore, you can provide specializations with a second template parameter (a formatting tag). The second template parameter defaults to Null_tag and means default behavior.

Specializations of Output_rep should provide the following features:

template< class F >
struct Output_rep< Some_type, F > {
  static const bool is_specialized = true;
  Output_rep( const Some_type& t );
  std::ostream& operator()( std::ostream& os ) const;
};

You can also specialize for a formatting tag F.

The constant is_specialized can be tested by meta-programming tools to verify that a given type can be used with oformat(). Its value has to be true in a specialization of Output_rep. When there is no specialization for a type, the class template Output_rep defines is_specialized to the default value false.

Public Member Functions
	Output_rep (const T &tt, F={})
	initialize with a const reference to t.
std::ostream &	operator() (std::ostream &os) const
	perform the output, calls operator<< by default.

Related Functions
(Note that these are not member functions.)
template<class T , class F >
std::ostream &	operator<< (std::ostream &os, Output_rep< T, F > rep)
	stream output of the Output_rep calls its operator().

Friends And Related Function Documentation

operator<<()

template<class T , class F >

std::ostream & operator<< ( std::ostream &  os, Output_rep< T, F >  rep  )

related

stream output of the Output_rep calls its operator().

CGAL defines output operators for classes that are derived from the class std::ostream. This enables to write to output streams as std::cout or std::cerr, as well as to std::ostringstream and std::ofstream. The output operator is defined for all classes in the CGAL Kernel and for the class Color as well.