Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

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Boost.Python

ResultConverter Concept

Introduction
Concept Requirements
ResultConverter Concept
ResultConverterGenerator Concept

Introduction

A ResultConverter for a type T is a type whose instances can be used to convert C++ return values of type T to_python. A ResultConverterGenerator is an MPL unary metafunction class which, given the return type of a C++ function, returns a ResultConverter for that type. ResultConverters in Boost.Python generally inspect library's registry of converters to find a suitable converter, but converters which don't use the registry are also possible.

Concept Requirements

ResultConverter Concept

In the table below, C denotes a ResultConverter type for a type R , c denotes an object of type C , and r denotes an object of type R.
Expression Type Semantics
C c; Constructs a C object.
c.convertible() convertible to bool false iff no conversion from any R value to a Python object is possible.
c(r) convertible to PyObject* A pointer to a Python object corresponding to r, or 0 iff r could not be converted to_python, in which case PyErr_Occurred should return non-zero.
c.get_pytype() PyTypeObject const* A pointer to a Python Type object corresponding to result of the conversion, or 0. Used for documentation generation. If 0 is returned the generated type in the documentation will be object .

ResultConverterGenerator Concept

In the table below, G denotes a ResultConverterGenerator type and R denotes a possible C++ function return type.
Expression Requirements
G::apply<R>::type A ResultConverter type for R.


Revised 09 May, 2002

© Copyright Dave Abrahams 2002.

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