typescript return type generics code example

Example 1: typescript generic class

class Person<T, U, C> {
  name: T
  age: U
  hobby: C[]

  constructor(name: T, age: U, hobby: C[]) {
    this.name = name
    this.age = age
    this.hobby = hobby
  }
}

const output = new Person<string, number, string>('john doe', 23, ['swimming', 'traveling', 'badminton'])
console.log(output)

Example 2: typescript generic type

function identity<T>(arg: T): T {
  return arg;
}Try

Example 3: 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