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Operators are the symbols (such as +, /, =, &) that perform a function. Operators are defined for Longs and Strings, but don't normally exist for user-defined types and classes. (It doesn't make much sense to do penguin3 = penguin1 + penguin2, right?) However, MBSC has ways of defining operators for UDTs and classes also. Using the same operator for multiple purposes or on multiple types is called operator overloading.
Let's jump straight into the code. This following code snippet overloads the '=' operator for Points and uses it to compare two points. The output is "-1", meaning true.
Type Point
Dim X as LONG
Dim Y as LONG
'Define the '=' operator with this function
FUNCTION OperatorEqual(P as Point) as LONG
OperatorEqual = X = P.X & Y = P.Y
END FUNCTION
End Type
SUB Main(Player as LONG)
Dim pntA as Point
Dim pntB as Point
pntA.x = 5
pntA.y = 7
pntB.x = 5
pntB.y = 7
PlayerMessage(Player, Str(pntA = pntB), Blue) 'Compare two Points and output result
END SUB
And, voilą! The "=" operator can be used for points! Operator overloading was first implemented in MBSC 2.0, about the same time as user-defined types.
The other overload functions are called: OperatorAdd (+), OperatorSubtract (-), OperatorMultiply (*), OperatorDivide (/), OperatorModulus (%), OperatorExponent (^), OperatorAnd (&), OperatorOr (|), OperatorGreaterThan (>), OperatorLessThan (<), OperatorEqualGreaterThan (>=), OperatorEqualLessThan (<=), and OperatorNotEqual (<>).