set types for function retur code example

Example 1: typescript function type

// define your parameter's type inside the parenthesis
// define your return type after the parenthesis

function sayHello(name: string): string  {
  console.log(`Hello, ${name}`!);
}

sayHello('Bob'); // Hello, Bob!

Example 2: get function return type typescript

type return_type = ReturnType<() => string>; // string
// or
function hello_world(): string {
  return "hello world";
}
type return_type = ReturnType<typeof hello_world>; // string