[C++-sig] test if object instance is instance of extension class in C++

[Stefan Seefeld]

On 2012-02-23 11:50, Holger Joukl wrote:
> Hi,
>
> what's the recommended way to check if an object instance is an instance of
> my extension class
> in C++ code?
>
> I'm currently doing a very ugly
>
> #define isMyExtensionClass(pyobj) (strcmp(pyobj->ob_type->tp_name,
> "MyExtensionClass") == 0)
>
> on PyObj* pyobj.
>
> I bet there is a better way but just can't seem to find it.

bpl::extract<MyExtensionClass> e(pyobj);
if (e.check()) ...

Note that you may want to use a reference type as template argument to
the boost::python::extract type, if you want to retrieve the object by
reference instead of by value.

See http://www.boost.org/doc/libs/1_40_0/libs/python/doc/v2/extract.html
for details.


HTH,
        Stefan


-- 

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