pxt-calliope/olddocs/js/code.md

function

A function with inputs and outputs.

@parent js/language

To add a functions to your script, click the script button, then click the + add new function button

functions

A function takes inputs, runs code and (optionally) returns an output.

TouchDevelop functions are similar to mathematical functions. Consider the function that computes the square of x: square(x) = x*x. In code, it would look like this:

export function square(x: number) : number {
    let result: number
    return x * x
    return result
}

private function

An function can be marked as private in the properties. A private function is not visible outside a library (if the script is a library)

documentation

The comment(s) at the beginning of a function used to provide a description of its purpose. This text will show in the help area when the function is called from the code editor. This is particularly useful for libraries.