It's been a while since I've programmed for school, and after picking up a copy of Sedgewick I decided to try out one of the problems for kicks. The class I wrote works great for concrete types, but when I tried to make a templated version I couldn't get it to link, as it couldn't resolve function calls to the templated class. Here's a stripped down version of the example.
Here's the makefile:
Code:
exe=polyadd
obj=polyadd.o polynomial.o
$(exe): $(obj)
c++ $(LDFLAGS) -o $(exe) $(obj)
polynomial.o: polyadd.c++ polynomial.c++
c++ $(CXXFLAGS) -c polynomial.c++
polyadd.o: polyadd.c++ polynomial.h
c++ $(CXXFLAGS) -c polyadd.c++
clean:
-rm -f $(obj) $(exe)
Here's the file
err.fuck after running the command
make 2>err.fuck
Code:
polyadd.o: In function `main':
polyadd.c++:(.text+0x124): undefined reference to `polynomial<int>::polynomial(std::vector<int, std::allocator<int> >&)'
polyadd.c++:(.text+0x137): undefined reference to `polynomial<int>::print(std::basic_ostream<char, std::char_traits<char> >&) const'
collect2: ld returned 1 exit status
make: *** [polyadd] Error 1
And here's the code:
Code:
/** polynomial.h */
#ifndef POLYNOMIAL_H
#define POLYNOMIAL_H
#include <vector>
using std::vector;
#include <ostream>
using std::ostream;
template <class T>
class
polynomial
{
public:
T& get_component (int n) const;
int degree () const;
polynomial (vector<T> &);
void print (ostream &) const;
private:
vector<T> p;
};
#endif
Code:
/** polynomial.c++ */
polynomial<T>::polynomial (vector<T> &v)
{
p = v;
}
template <class T>
T&
polynomial<T>::get_component (int n) const
{
return p [n];
}
template <class T>
int
polynomial<T>::degree () const
{
return p.size ()-1;
}
template <class T>
void
polynomial<T>::print (ostream &os) const
{
if (p.size ()==0)
return;
else if (p.size ()==1)
os << p[0];
else {
os << p[0] << " + ";
for (int i=1; i < degree (); i++)
os << p[i] << "x^" << i << " + ";
os << p [degree ()] << "x^" << degree ();
}
}
Code:
/** polyadd.c++ */
#include <iostream>
using std::cout;
using std::endl;
using std::cerr;
#include "polynomial.h"
#include <vector>
using std::vector;
int
main (int argc, char *argv [])
{
vector<int> v;
v.push_back (1);
v.push_back (2);
v.push_back (3);
v.push_back (4); // 1 + 2x + 3x^2 + 4x^3
for (int i=0; i<v.size (); i++)
cout << v[i] << " ";
cout << endl;
polynomial<int> p(v);
p.print (cout);
return 0;
}
Please tell me I'm just doing something stupid. I remember doing stuff like this in Visual C++ for my class. I've tried it under gcc-4.0.3 and gcc-3.3.6, and the output I posted is from compiling with gcc-4.0.3.
Thanks
