Typescript type a function property 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

interface Date {
  toString(): string;
  setTime(time: number): number;
  // ...
}