2797. 带有占位符的部分函数

2797. 带有占位符的部分函数

type JSONValue =
  | null
  | boolean
  | number
  | string
  | JSONValue[]
  | { [key: string]: JSONValue }
type Fn = (...args: JSONValue[]) => JSONValue

function partial(fn: Fn, args: JSONValue[]): Fn {
  return function (...restArgs) {
    let _args = args.map((item) => {
      if (restArgs.length > 0 && item === '_') {
        return restArgs.shift()
      }
      return item
    })
    if (restArgs.length > 0) {
      _args = _args.concat(restArgs)
    }
    return fn(...(_args as JSONValue[]))
  }
}