javascript - 打印出迭代中的每个数组值，值是未定义的

Question

我想打印出组合数组的内容。正如您所看到的，我在代码末尾调用了console.log，并且组合数组中的每个值都是未定义的。但是，如果我在其他地方(例如 if 语句)调用 console.log ，则值是正确的。请告诉我原因，谢谢!

$(function() {
  var text = $('p').text().split('');
  var letter = 0;
  var composed = [];
  $.each(text, function(index, value) {
    if (/\w/.test(value)) { // if the character is alphanumeric
      var prev = index - 1;
      var next = index + 1;
      if (/\w/.test(text[prev])) {
        composed[letter] = composed[letter] + value;

        if (!/\w/.test(text[next])) {
          console.log('composed[' + letter + '] = ' + composed[letter]);
          letter++;
        }
      } else {
        composed[letter] = value;

        if (!/\w/.test(text[next])) {
          console.log('composed[' + letter + '] = ' + composed[letter]);
          letter++;
        }
      }
    } else {
      composed[letter] = value;
      console.log('composed[' + letter + '] = ' + composed[letter]);
      letter++;
    }
    console.log('composed[' + letter + '] = ' + composed[letter]); // undefined
  });
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<p>Test both Chinese中文 ,alphbets and numbers.</p>

<小时/>

Answer 1

console.log('composed[' + letter + '] = ' + composed[letter - 1]);

这给出了正确的值