Creating void functions in TypeScript

I encountered a section of code within a custom component that is proving to be quite puzzling for me to comprehend. 

public onTouch: () => void = () => {}

The function onTouch is being assigned by the private method 

registerOnTouch(fn: any) {
  this.onTouch = fn;
}

My understanding is that the initial part public OnTouch: () = void indicates a parameterless function that doesn't return anything. However, I am struggling to grasp the significance of the concluding part () => ().

Can someone clarify what the latter portion signifies? Could it potentially be an overload?

typescript

Answer №1

In the beginning:

() => void

defines the function type onTouch and followed by:

= () => {}

specifies its default value. Essentially, if onTouch is not given a different value, it will be an empty function.

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