小编mar*_*tte的帖子

我知道,这是一个奇怪的!但为什么这不起作用？

function getStringLength(string) {

  // see how many substrings > 0 can be built
  // log that number & return

  var subString = string.slice();
  var counter = 0;

  while (subString !== '') {
    counter++;
    subString = subString.slice(counter);
  }

  return counter;
}

var output = getStringLength('hello');

console.log(output); // --> expecting 5, but getting 3 (??)

我真的想用切片来做!最初的挑战是不使用length属性,我想出来了,这很好用:

function getStringLength(string) {

  var long = 0;

  while (string[long] !== undefined) {
    long++;
  }

  return long;
}

var numbers = [5, 3, 8, 6, 9, 1, 0, 2, 2];
var oddEvenCounts = numbers.reduce(function(counts, number) {
  if (isOdd(number)) {
    counts[odd]++;
  } else {
    counts[even]++;
  }
}, {});

我正在寻找这段代码中的错误(仍在学习reduce方法;)) - 我哪里出错了？