typescript return a function with parameter types from parameter code example

Example 1: typescript default parameter

// Default Parameters
sayHello(hello: string = 'hello') { 
    console.log(hello); 
}

sayHello(); // Prints 'hello'

sayHello('world'); // Prints 'world'

Example 2: 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!