var arr = [1, 2, 3,[false], ['hello']];
var arr2 = [].concat.apply([], arr);
console.log(arr2); // [ 1, 2, 3, false, 'hello' ]
var arr = [1, 2, 3,[false], ['hello']];
var arr2 = [].concat.apply([], arr);
console.log(arr2); // [ 1, 2, 3, false, 'hello' ]