CGAL users discussion list

[Tom Bobach <>]

Dear CGAL community,

I am facing the problem that in the default halfedge data structure 
implementation there is no comparison operator defined for handles and 
iterators.
This makes usage of Handles in std::set and std::map unnecessarily 
complicated. I am wondering if someone else faced this problem and if there 
is an easy, non-intrusive way to fix this.


Thanks a lot!

        Tom


As an illustration, the following won't work:

============ <CODE: main.cpp> =============

#include <CGAL/Simple_cartesian.h>
#include <CGAL/Polyhedron_3.h>
#include <set>

struct K : public CGAL::Simple_cartesian<double> {};
struct Poly : public CGAL::Polyhedron_3<K> {};

int main()
{
    Poly::Vertex_const_handle h;
    std::set<Poly::Vertex_const_handle> s;

    s.insert( h );
}

============ </CODE: main.cpp> =============


============ <ERROR MESSAGE> =============

<... lots of template error messages ...>
main.cpp:13:   instantiated from here
/usr/lib/gcc/i686-pc-linux-gnu/4.1.1/include/g++-v4/bits/stl_function.h:227: 
error: no match for 'operator<' in '__x < __y'
make: *** [main.o] Error 1

============ </ERROR MESSAGE> =============

-- 
Dipl. Inform Tom Bobach, University of Kaiserslautern
Geometric Algorithms Group
P.O. Box 3049
D-67653 Kaiserslautern
Germany
Phone: 0631-205 3800
Fax: 0631-205 3270