How do I call a function defined in C++ object from a python program?

Question

I have a C++ program:

class X
{
 private:
 int a;
 public:
 int func(char *str);
};

Now I want to call the function func in my Python program. How can I do it?

I have successfully called C functions from my Python program using ctypes. However I can't seem to figure out how to call functions defined inside C++ objects.

I have already worked with ctypes, so I would like to figure out how to accomplishing it that way. However I'm open to other techniques. Also my project puts a constarint that I am not supposed to use wrapper function in my C++ program.

• Karl Knechtel: Who thinks this is "not a real question"? Why?

Answer 1

Check out Boost::Python.

• Sudip: thank you friend.. but I am not supposed to write wraaper functions which i will need to write in boost Python..
• Karl Knechtel: "supposed to"? Isn't it your project?

Answer 2

You tagged the question ctypes, but you cannot instantiate a C++ object directly from ctypes. You can wrap the C++ object in a C interface and then use ctypes. Or you could write a Python extension module which could include C++ code.

• Sudip: You mean to say i first need to study writing python extension module(I am not supposed to use wrapper functions) to accomplish my task..
• David Heffernan: Your question says nothing about these extra constraints you are adding in comments. Please can you correct the question.
• Sudip: I have edited my question to include my constraint. Now, can you advice me on how to move forward.
• David Heffernan: Your options are 1. Wrap the C++ code in a C style wrapper. 2. Write an extension module. SWIG and Boost.Python both make it easier for you to create an extension module.

Answer 3

An alternative to Boost.Python is SWIG.

Answer 4

try http://swig.org/ years ago i wrapped some c/c++ code to use them in wxPython with swig. i cannot remember too much details but i think swig is easy to use.

Hope that helps.