[C++-sig] from_python non-compiletime-constant

[David Abrahams]

Neal Becker <ndbecker2 at gmail.com> writes:

> I need to register a from_python conversion where the type object is not a
> compile constant.  I'm trying to write c++ code that will accept a numpy
> array.
>
> AFAICT, the PyTypeObject addresses aren't known at compile time, so can't be
> used in lvalue_from_pytype template arguments.  These pointers can be found
> at runtime.  How do I handle this?

Just take apart the implementation of lvalue_from_pytype and you'll
find lower-level facilities in use that will let you build a similar
converter.  Unfortunately the code for lvalue_from_pytype is pretty
convoluted but I've posted the solution several times before on this
list so you should be able to find it.

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com