TypeScript (81)

Which of the given parameters are optional?

function get(start: number, limit: number, query: string = "", sortBy?: string) {
}

 start

 limit

 query

 sortBy

Does TypeScript allow to pass more arguments than is defined in a function declaration (will not throw any errors during compilation)?

function show (a: string) {
  console.log(a);
}
console.log(show("hello", "world"));

 yes

 no

What will the following code output to the console?

function add (x: number, y: number = 1): number {
  return x + y;
}
console.log(add(15, undefined));

What will the following code output to the console?

function subtract(x: number = 10, y: number = 5): number {
  return x - y;
}
console.log(subtract(7, null));

What will the following code output to the console?

function add(x: number = 10, y: number = 5): number {
  return x + y;
}
console.log(add(20));

In TypeScript, by default, each function parameter is optional. True or false?

 true

 false

Which of the following types should be chosen for returned type if a function doesn't return anything in TypeScript?

 null

 undefined

 string

 void

When we create a function in TypeScript a returned data type annotation is required. True or false?

public get(start: number, limit: number): string[] {}

 true

 false

Is it possible to use generic type parameter in static class members?

class Collection<T> {
  static type: T;
}

 yes

 no

Is this code a correct example of using generics in TypeScript (we get no errors during compilation)?

class Collection<T> {
  items: T[];
  find(keyword: string) : T {
    return this.items.filter(el => el.value === keyword)[0];
  }
}

 yes

 no