From Xojo Documentation
The ordinary (left) methods are always preferred; the Right version is used only if there is no legal left version.
Suppose you have a class, Vector, that can store a vector of modest size. To define the + operator for this class, create a method of the Vector class called Operator_AddRight.
The Vector class has two integer properties, x and y.
Operator_AddRight is defined as:
// lhs stands for left-hand-side, the vector to be added to Self
Var ret As New Vector // the sum of the two vectors
ret.x = lhs.x + Self.x
ret.y = lhs.y + Self.y