c++ - Execute python function with boost-python (not global scope statements) -

i've question regarding boost-python. want execute specific python function stored in std::string boost-python. there example how achieve in documentation: boost python doc.

so i'm doing (c++ code):

using namespace boost::python; py_initialize();  // retrieve main module. object main = import("__main__");  // retrieve main module's namespace object global(main.attr("__dict__"));  // define greet function in python. object result = exec(string_with_python_code.c_str(), global, global);  object greet = global["greet"];  //calling greet() function greet();  py_finalize(); 

however, executes code not in function in global scope (contrary statement in documentation says above exec() statement: "[only] define greet function in python").

for example if set python code in string_with_python_code this:

string_with_python_code = "print 'hello global world!'    \n"                           "                               \n"                           "def greet():                   \n"                           "    print 'hello local world!' \n"                           "    return                     \n"; 

then sentence "hello global world!" printed out (before "hello local world!" printed out).

however, hoped accomplish function greet() gets executed. how can achieve this?

a python function definition execution of python code. python module import: importing module can cause arbitrary python statements run.

the way not run code outside function definition not pass code outside function definition exec. exec tell do, no less.