Function runOnce

Runs a function once

const init = runOnce(() => {
 // do some initialisation
});

init(); // Runs once
init(); // no-op

runOnce(onRun): (() => boolean)
Parameters
- onRun: (() => boolean)
  - - (): boolean
    - Returns boolean
Returns (() => boolean)
- - (): boolean
  - Returns boolean