Functions

Functions are blocks of code that execute a set of pre-defined tasks that can be ran at any point in code execution.

Declaring a function

A function can be declared by using the event statement followed by a name and its arguments. Similar to variables, arguments can store any value, including other functions.

// This function has 2 arguments that get multiplied, the result is then printed to the screen.
event multiplyAndPrint(a, b) {
    print(a * b);
}

Functions can then be called from anywhere as long as it is in same scope by writing the name and required arguments of the function. Calling a function will execute any code stored inside of it.

multiplyAndPrint(4, 2);

INFO: 8

As mentioned in Variables, functions are like any other type, meaning you can assign them to a variable. You can do so by setting the variable to the function's name, omitting its arguments.

var functionVariable = multiplyAndPrint;

After assigning a function to a variable, it can be called by using the variable's name.

functionVariable(4, 8);

INFO: 32

Optional arguments

An optional argument is a function argument with a default value that gets used in the case a value isn't specified in the function call. You can declare an optional argument by using the = sign after the argument name. Optional arguments can only be declared after the required arguments.

event countToNumberInSteps(max, steps = 1) {
    repeat(max, count) {
        if (count % steps != 0) {
            continue;
        }
        print(count);
    }
}

Optional arguments can also be defined by using the [] syntax.

// If we don't specify a default value, it'll default to NULL.
event countToNumberInSteps(max, [steps = 1]) {
    repeat(max, count) {
        if (count % steps != 0) {
            continue;
        }
        print(count);
    }
}

If we call this function without specifying the optional argument, it will default to counting in steps of 1 but we can also specify the step count to any arbitrary number we want.

print("Without specifying a step.");
countToNumberInSteps(6);
print("When specifying a step.");
countToNumberInSteps(6, 2);

INFO: Without specifying a step.
INFO: 0
INFO: 1
INFO: 2
INFO: 3
INFO: 4
INFO: 5
INFO: When specifying a step.
INFO: 0
INFO: 2
INFO: 4
INFO: 6

Return values

Functions can optionally return any value at any point in its execution. You can specify a return value by using the return statement.

event multiply(a, b) {
    return a * b;
}
 
var result = multiply(2, 5);
print(result);
 
print(multply(result, 2));

INFO: 10
INFO: 20

return statements will completely stop the execution of a function, which means that any code after the return statement won't get ran.

event sendMessage(message = "Hello") {
    print("This is my message: " + message);
    // Returns nothing.
    return;
    print("I won't get printed :C");
}
 
sendMessage("Hello, reader!");

INFO: This is my message: Hello, reader