Check out example codes for "full call signature in ts". It will help you in understanding the concepts better.

Code Example 1

// shorthand call signature
type Greet = (name: string) => void
//OR
//full call signature 
type Greet = {
  {name: string) => void }
  }

let greet: Greet = (name) =>{
  console.log('My name is ' , name)
};

greet('joyous jackal')  // My name is joyous jackal

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