015.ReplaceAll

实现 ReplaceAll<S, From, To>，将一个字符串 S 中的所有子字符串 From 替换为 To

例如：

type replaced = ReplaceAll<'t y p e s', ' ', ''> // 期望是 'types'

答案

type ReplaceAll<S extends string, From extends string, To extends string> = From extends ''
  ? S
  : S extends `${infer L}${From}${infer R}`
    ? `${L}${To}${ReplaceAll<R, From, To>}`
    : S

注意，下面写法是不对的：

type ReplaceAll<S extends string, From extends string, To extends string> = From extends ''
  ? S
  : S extends `${infer L}${From}${infer R}`
    ? ReplaceAll<`${L}${To}${R}`, From, To>
    : S

这会导致 From 匹配到上个递归 To 中的字符