TypeScript

TypeScript Playground https://www.typescriptlang.org/play/

var title: string = 'niko angular';
//title = 1; 型エラー

title = 'moge'

var isOpen: boolean = true;

var array: string[] = ['aaa', 'bbbbb'];
var data: [number, string, number] = [1, "b", 1];

var options: { [key: string]: string; };

options={ name: "yuhiisk" ,name1:"1111"};

var moko = 1;
//moko = ''; 初期化時に数値型となっているので型エラー


function greet(name: string="zzz") : string{
    return "aa=" + name;
}

document.write(greet());