Function equivalent

edrav2/eprj/boost/libs/python/src/numpy/dtype.cpp:103–130

int dtype::get_itemsize() const { return reinterpret_cast<PyArray_Descr*>(ptr())->elsize;}

bool equivalent(dtype const & a, dtype const & b) {
    // On Windows x64, the behaviour described on 
    // http://docs.scipy.org/doc/numpy/reference/c-api.array.html for
    // PyArray_EquivTypes unfortunately does not extend as expected:
    // "For example, on 32-bit platforms, NPY_LONG and NPY_INT are equivalent".
    // This should also hold for 64-bit platforms (and does on Linux), but not
    // on Windows. Implement an alternative:
#ifdef _MSC_VER
    if (sizeof(long) == sizeof(int) &&
        // Manually take care of the type equivalence.
        ((a == dtype::get_builtin<long>() || a == dtype::get_builtin<int>()) &&
         (b == dtype::get_builtin<long>() || b == dtype::get_builtin<int>()) ||
         (a == dtype::get_builtin<unsigned int>() || a == dtype::get_builtin<unsigned long>()) &&
         (b == dtype::get_builtin<unsigned int>() || b == dtype::get_builtin<unsigned long>()))) {
        return true;
    } else {
        return PyArray_EquivTypes(
            reinterpret_cast<PyArray_Descr*>(a.ptr()),
            reinterpret_cast<PyArray_Descr*>(b.ptr())
        );
    }
#else
    return PyArray_EquivTypes(
        reinterpret_cast<PyArray_Descr*>(a.ptr()),
        reinterpret_cast<PyArray_Descr*>(b.ptr())
    );
#endif
}

namespace
{