Print Boost Python object

Question

I have a Boost Python object

py::object obj = whatever();

I want to print it using normal python rules.

// I want the effect of print 'My object is ', obj
std::cout << "My object is " << obj << std::endl;

This does not compile with a huge compiler dump. How do I do this?

I'm not that familiar with Boost.Python, but I am not sure it has an operator<<(ostream &) defined for py::object. — nneonneo
– nneonneo, Commented Dec 16, 2014 at 19:44
You'd probably just want to write the equivalent code to call Python's str() function passing obj as the argument, and convert the return value to an std::string, and stream that out. You could provide your own operator<<(ostream &, py::object const &) to provide the streaming operator for all Python objects using this approach. — cdhowie
– cdhowie, Commented Dec 16, 2014 at 19:45

Barry · Accepted Answer · 2014-12-16 19:52:56Z

11

Boost.Python doesn't come with an operator<<(ostream&, const object&) but we can write our own to mimic what Python would do natively: call str:

namespace py = boost::python;

std::ostream& operator<<(std::ostream& os, const py::object& o)
{
    return os << py::extract<std::string>(py::str(o))();
}

answered Dec 16, 2014 at 19:52

Barry

312k32 gold badges734 silver badges1.1k bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Print Boost Python object

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related