Swift-operator overloading and operator functions

It is called operator overloading to have an existing operator operate on a custom class and struct or redefine an operation rule for an existing operator.

1, add the custom two coordinate structure body objects by overloading the plus operator:

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struct CenterPointer{    var x=0, y=0}func + (left:CenterPointer, right:CenterPointer) -> CenterPonter{    return CenterPointer(x:left.x+right.y, y:left.y+right.y)}let pointer1 = CenterPointer(x:2, y:3)let pointer2 = CenterPointer(x:4, y:5)let pointer3 = pointer1 + pointer2

 

2, overload judgment operator for determining whether custom types are equal

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func == (left:CenterPointer, right:CenterPointer) -> Bool {    return (left.x == right.x) && (left.y == right.y)}func != (left:CenterPointer, right:CenterPointer) -> Bool {    return !(left == right)}

 

3, combining operators, combining other operators and assignment operators, note to set the operator left argument to the InOut type

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func+= (inout left:CenterPointer, right:CenterPointer){    left = left + right} var pointer1 = CenterPointer(x:2, y:3)varpointer2 = CenterPointer(x:4, y:5)pointer1 += pointer2

Swift-Operator overloading and operator functions