Nic Roets wrote:
Often when I write searching or sorting code in C or C++, I'm frustrated that I have to make a new "callback type" compare function. E.g. when you want to sort a number of points in 2D space according to their distance from a reference point, it's tempting to do something like
struct Pt { int x, y; };
static Pt center; // Global or static variable yuck.
int PtDistToCenterCmp (Pt &a, Pt &b) { return Dist (a, center) - Dist (b, center); }
main() { ... center.x = ...; center.y = ...; ... sort (...); ... }
This type of solution has many problems.
int PtDistToCenterCmp( Pt const & a, Pt const & b, Pt const & center ) { return Dist (a, center) - Dist (b, center); } int main() { sort( first, last, boost::bind( PtDistToCenterCmp, _1, _2, center ) ); }