Array.prototype.shift

var arr = ["1", "2"];
var hoge = arr.shift();

// hoge = "1", arr = ["2"]

関連

• [Array.prototype.unshift() - JavaScript

  MDN](https://developer.mozilla.org/ja/docs/Web/JavaScript/Reference/Global_Objects/Array/unshift)

  • 配列の戦闘に要素を追加する