Compare/Copy COORD struct; overloading

This seems trivial yet endless searching doesn't yield an answer.

I need to compare and assign.

How can I overload the COORD if I can't add a member function or friend a function?

is it just开发者_开发知识库 bad style to use this windows based structure?

Also, I know I can write my own class(or just do the operation once for each member), but this problem just really has me wondering.

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COORD only has public members, so there's no need for friend functions -- free operators should suffice:

bool operator <(COORD const& lhs, COORD const& rhs)
{
    return lhs.Y < rhs.Y || lhs.Y == rhs.Y && lhs.X < rhs.X;
}

bool operator ==(COORD const& lhs, COORD const& rhs)
{
    return lhs.X == rhs.X && lhs.Y == rhs.Y;
}

COORD has an implicit copy c'tor and operator= already, no need to define those.

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Why not derive your on class from public COORD and add the required statements? struct in C++ is just the same as class, except that by default all members are public.

struct MyCoord : public COORD
{
  // I like to have a typedef at the beginning like this
  typedef COORD Inherited;
  // add ctor, if you like ...
  MyCoord(SHORT x, SHORT y)
    : Inherited::X(x)
    , Inherited::Y(y)
  { }
  // no need for copy ctor because it's actually POD (plain old data)

  // Compatibility ... ;)
  operator COORD&()
  {
      return *this; // may need cast
  }

  COORD* operator&()
  {
     return this; // may need cast
  }
  // declare friends ...
}