Re: comparison operator for STL sets

Hello,
The comparator functor one specifies when declaring a stl set should
follow strict weak ordering semantics. This means it should return
true if x is strictly less than y, otherwise false. And equivalance is
tested as x == y iff. !(x < y) and ! (y < x). If this is met then
set.insert() will fail since there is such an element already. What
about the case where it turns out (x < y) and ( y < x) is true,

should such an element be inserted? Logically this should never
happen, but I ran into this in code below:

struct MyClass {
  MyClass(int num,char *name): _num(num){
    strlcpy(_name,name,sizeof _name);
   }

  int _num;
  char _name[NAME_LEN+1];

};

class MyClassCompare{
public:
  bool operator()(const MyClass& lhs,const MyClass& rhs) const{
    if(lhs._num < rhs._num)
      return true;
    else {
      if(strncmp(lhs._name,rhs._name,NAME_LEN+1) < 0)
    return true;
    }
    return false;
  }