let len: number = (input as string).length

let len: number = (<string> input).length  /* not allowed in JSX */

​

// cheatsheets for typescript

https://devhints.io/typescript

// Primitive types

let num: number = 42;

let str: string = "Hello, TypeScript";

let bool: boolean = true;

​

// Arrays

let arr: number[] = [1, 2, 3];

let strArr: string[] = ["a", "b", "c"];

​

// Tuples

let tuple: [number, string] = [1, "one"];

​

// Enums

enum Color {

    Red,

    Green,

    Blue,

}

let chosenColor: Color = Color.Green;

enum Color {Red, Green, Blue = 4}

let c: Color = Color.Green

​