🔒 Locked

operator error help

Started by mike25025 Mar 10, 2005 at 11:31 PM 2 replies 400+ views

Original Post

Mar 10, 2005 at 11:31 PM

im getting this error

error: passing `const SVector' as `this' argument of `SVector SVector::operator-(const SVector&)' discards qualifiers

in this code

SVector operator-(const SVector& v)
{
	return SVector(x-v.x,y-v.y,z-v.z);
}

i know theres a simple solution but i dont know what it is thanks for any help

Evil Steve

382

Evil Steve

Mar 10, 2005 at 11:50 PM

SVector operator-(const SVector& v){	return SVector(x-v.x,y-v.y,z-v.z);}

Should be:

SVector operator-(const SVector& v) const{	return SVector(x-v.x,y-v.y,z-v.z);}

Note the additional const. This lets the compiler know that it's operating on a const object

Washu

Mod

375

Washu

Mar 10, 2005 at 11:54 PM

Another note: You really should define operator- in terms of operator -=. In other words:

CVector operator-(CVector const& lhs, CVector const& rhs) {  return CVector(lhs) -= rhs;}

Jingo

Mar 11, 2005 at 1:19 AM

Quote:
Original post by Washu
Another note: You really should define operator- in terms of operator -=. In other words:
CVector operator-(CVector const& lhs, CVector const& rhs) {  return CVector(lhs) -= rhs;}

You should really define operator- in terms of expression templates.

Topic Locked

This topic has been locked by a moderator. New replies are not allowed.