SWIG: AttributeError: object 'module' does not have attribute 'fact'

Question

I am learning how to use swig to make a C extension for my Python code. And I use the code that I get from the website as an example. Here is my code:

example.c

 #include <time.h>
 double My_variable = 3.0;

 int fact(int n) {
     if (n <= 1) return 1;
     else return n*fact(n-1);
 }

 int my_mod(int x, int y) {
     return (x%y);
 }

example.h

#ifndef EXAMPLE_H_
#define EXAMPLE_H_

 extern double My_variable;
 extern int fact(int n);
 extern int my_mod(int x, int y);

#endif

example.i

%module example
 %{
 /* Put header files here or function declarations like below */
#define SWIG_FILE_WITH_INIT
    #include "example.h"
 %}

%#include "example.h"

Makefile

all:
    rm -f *.so *.o *_wrap.* *.pyc
    swig -python example.i
    gcc -c -fPIC example_wrap.c -I/usr/include/python2.7
    gcc -shared  example_wrap.o -o _example.so

clean:
    rm -f *.so *.o *_wrap.* *.pyc

test.py

import example

print str(example.fact(2))

Test.py is used to check if the extension is working. But when I run test.py, it outputs:

Traceback (most recent call last):
  File "test.py", line 3, in <module>
    print str(example.fact(2))
AttributeError: 'module' object has no attribute 'fact'

Here is the result when I use dir (example):

['__builtins__', '__doc__', '__file__', '__name__', '__package__', '_example', '_newclass', '_object', '_swig_getattr', '_swig_property', '_swig_repr', '_swig_setattr', '_swig_setattr_nondynamic']

What is the reason for this conclusion?

If I want the program to run successfully, how do I do it?

Answer 1

Please try replacing as below:

%#include "example.h"

by

%include "example.h"

Answer 2

Link

Try changing the Makefile to

%module example
%{
   #include "example.h" 
%}
int fact(int n);

I suggested that you have only one way to export