CGAL users discussion list

["Jannis Warnat" <>]

Hello,

 

I am experimenting with the Arrangement_2 demo. When I exchanged the use of Arr_segment_traits_2 to Arr_linear_traits_2 the following function from the file demo_tab.h didn´t work anymore:

 

void

draw_xcurve(Qt_widget_demo_tab<Segment_tab_traits> * w, X_monotone_curve_2 c)

{

(*w) << c;

}

 

I got the following compiler errors:

 

../../include/CGAL/Arr_linear_traits_2.h:1705: error: no match for 'operator<<' in 'os << " P "'

../../include/CGAL/Arr_linear_traits_2.h:1707: error: no match for 'operator<<' in 'os << " S "'

../../include/CGAL/Arr_linear_traits_2.h:1709: error: no match for 'operator<<' in 'os << " R "'

../../include/CGAL/Arr_linear_traits_2.h:1711: error: no match for 'operator<<' in 'os << " L "'

 

Here is the code snippet from Arr_linear_traits_2.h:

 

template <class Kernel, class OutputStream>

OutputStream& operator<< (OutputStream& os,

const Arr_linear_object_2<Kernel>& lobj)

{

// Print a letter identifying the object type, then the object itself.

if (lobj.is_point())

os << " P " << lobj.point();

else if (lobj.is_segment())

os << " S " << lobj.segment();

else if (lobj.is_ray())

os << " R " << lobj.ray();

else

os << " L " << lobj.line();

return (os);

}

 

It works fine if I comment out the letters, e.g. change

 

os << " P " << lobj.point();

 

to

 

os << /*" P " <<*/ lobj.point();

 

Not sure if this is valuable information to you.

 

Sincerely,

 

Jannis Warnat