Having trouble Generating Wrapper function using Swig for C++ template - swig

Question

I am trying to use swig to generate interface on some existing C++ methods. I am referring to the following link for practice to generate on c++ template methods
https://valelab4.ucsf.edu/svn/3rdpartypublic/swig/Examples/python/template/
File : example.h
// Some template definitions
template<class T> T max(T a, T b) { return a>b ? a : b; }
template<class T> class vector {
T *v;
int sz;
public:
vector(int _sz) {
v = new T[_sz];
sz = _sz;
}
T &get(int index) {
return v[index];
}
void set(int index, T &val) {
v[index] = val;
}
#ifdef SWIG
%extend {
T getitem(int index) {
return $self->get(index);
}
void setitem(int index, T val) {
$self->set(index,val);
}
}
#endif
};
File : example.i
%module example
%{
#include "example.h"
%}
/* Let's just grab the original header file here */
%include "example.h"
/* Now instantiate some specific template declarations */
%template(maxint) max<int>;
%template(maxdouble) max<double>;
%template(vecint) vector<int>;
%template(vecdouble) vector<double>;
setup.py
from distutils.core import setup, Extension
#name of module
name = "example"
#version of module
version = "1.0"
# specify the name of the extension and source files
# required to compile this
ext_modules = Extension(name='_example',sources=["example.i","example.h"])
setup(name=name,
version=version,
ext_modules=[ext_modules])
step 1: compile module
python setup.py build_ext
step 2: install in the current directory
python setup.py install --install-platlib=.
I am seeing the following errors as the output
python setup.py build_ext
running build_ext
building '_example' extension
swigging example.i to example_wrap.c
swig -python -o example_wrap.c example.i
example.h:5: Warning 301: class keyword used, but not in C++ mode.
example.h:5: Error: Syntax error - possibly a missing semicolon.
error: command 'swig' failed with exit status 1

Answer 1

Use the following in setup.py to pass the -c++ option to SWIG. Also remove example.h from sources or the compiler tries to compile the header. It's already included in the generated file.
ext_modules = Extension(name='_example', sources=["example.i"], swig_opts=['-c++'])