javascript - 如何让这个程序化 JS 变得更加实用呢？

Question

鉴于此函数根据用户设置对数组重新排序...

function getDayNamesInUserOrder() {

    var dayNames = ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'];
    var weekStartDayIndex = 2; // user has set this to be 2 (Tuesday)

    // remove the first n days from the front of the array...
    var daysSlicedFromStart = dayNames.splice(0, weekStartDayIndex);

    // and stick them onto the end of it.
    var dayNamesInUserOrder = dayNames.concat(daysSlicedFromStart);

    return dayNamesInUserOrder;
}

getDayNamesInUserOrder();
=> ['Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun', 'Mon']

如何在使用更少的状态和变量的同时使其功能更强大？

Answer 1

这个怎么样？

function getDayNamesInUserOrder(offset) {
  var dayNames = ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'];
  return [0,1,2,3,4,5,6].map(function (i) {
    return dayNames[(i+offset) % 7];
  });
}