[Intermediate Algorithm Scripting: Spinal Tap Case | freeCodeCamp.org](https://www.freecodecamp.org/learn/javascript-algorithms-and-data-structures/intermediate-algorithm-scripting/spinal-tap-case)

```js function spinalCase(str) { return str }

spinalCase('This Is Spinal Tap') ```

```js str = str.replace(/([a-z])([A-Z])/g, '$1 $2') ```

这一句是我不会的地方。主要涉及正则表达式的使用。

答案：

```js function spinalCase(str) { let regex = /\s+|_+/g str = str.replace(/([a-z])([A-Z])/g, '$1 $2') return str.replace(regex, '-').toLowerCase() }

console.log(spinalCase('ThisIsSpinalTap')) ```

```js function spinalCase(str) { / Replace low-upper case to low-space-uppercase str = str.replace(/([a-z])([A-Z])/g, '$1 $2') / Split on whitespace and underscores and join with dash return str .toLowerCase() .split((?:_| )+) .join('-') } ```

```js function spinalCase(str) { / "It's such a fine line between stupid, and clever." / –David St. Hubbins

return str .split(\s|_|(?=[A-Z])) .join('-') .toLowerCase() } ```