Spinal Tap Case

将字符串转换为 spinal case。Spinal case 是 all-lowercase-words-joined-by-dashes 这种形式的，也就是以连字符连接所有小写单词。

这是一些对你有帮助的资源:

• RegExp

• String.replace()

之前卡在这道题上了，现在搜到一个答案，先来充数

function spinalCase(str) {
  return str.replace(/_/g," ").replace(/([A-Z])/g," $1").replace(/^s/,"").replace(/s+/g,"-").toLowerCase();
}

 方法二：

function spinalCase(str) {
  // "It's such a fine line between stupid, and clever."
  // --David St. Hubbins
  var reg = /s|\_/g;
  var str = str.replace(/([a-z])([A-Z])/g,'$1 $2');
  str = str.toLowerCase().replace(reg,'-');
  return str;
}