Boost.Python

Contents

Introduction

keyword-expressions

Classes

class arg

class arg synopsis

class arg constructor

class arg template operator =

Keyword-expression operator ,

Example(s)

Introduction

Supplies a family of overloaded functions for specifying argument keywords for wrapped C++ functions.

keyword-expressions

A keyword-expression results in an object which holds a sequence of ntbses, and whose type encodes the number of keywords specified. The keyword-expression may contain default values for some or all of the keywords it holds

Classes

class arg;

The objects of class arg are keyword-expressions holding one keyword ( size one )

Class arg synopsis

namespace boost { namespace python
{
	struct arg 
	{
	  template <class T>
		  arg &perator = (T const &value);
	  explicit arg (char const *name){elements[0].name = name;}
	};

}}

Class arg constructor

arg(char const* name);

Requires: The argument must be a ntbs.

Effects: Constructs an arg object holding a keyword with name name.

Class arg operator =

template <class T> arg &operator = (T const &value);

Requires: The argument must convertible to python.

Effects: Assigns default value for the keyword.

Returns: Reference to this.

Keyword-expression operator ,

      keyword-expression operator , (keyword-expression, const arg &kw) const
      keyword-expression operator , (keyword-expression, const char *name) const;

Requires: The argument name must be a ntbs.

Effects: Extends the keyword-expression argument with one more keyword.

Returns: The extended keyword-expression.

Example

#include <boost/python/def.hpp>
using namespace boost::python;

int f(double x, double y, double z=0.0, double w=1.0);

BOOST_PYTHON_MODULE(xxx)
{
   def("f", f
            , ( arg("x"), "y", arg("z")=0.0, arg("w")=1.0 ) 
            );
}

Revised 05 November, 2001

© Copyright Dave Abrahams 2002. All Rights Reserved.