Skip to main content

Callbacks

A callback is a method passed as an argument to another method. In Morph, use the method type for callback parameters.

Declaring a Callback Parameter​

Execute method(action as method) {
    action();
}

The parameter action has type method — it accepts any callable.

Calling with a Named Method​

SayHello method() {
    Print("Hello!");
}

Execute(SayHello);   // prints "Hello!"

Calling with a Lambda​

Execute(method() {
    Print("Lambda executed!");
});

Callback with Return Value​

Compute method(op as method) as int {
    return op();
}

result is Compute(method() as int {
    return 42;
});

Print(result);   // 42

Pattern: Event Handlers​

OnClick method(handler as method) {
    // ... when click detected:
    handler();
}

OnClick(method() {
    Print("Button clicked!");
});

Next Steps​