TYPESCRIPT

contextual typing in typescript

Lets say you defined a call signature for any function.

type greet = (name: string) => void 

Now, when you declare any function having this type, like this

const sayHello: greet = (name) =>{
  console.log("hello ", name);
}

you dont need to explicitly annotate funciton paramters and return type,
  this is called "CONTEXTUAL TYPING".