import { curryN } from "@unboxing/function"
import { ArrPred } from '@unboxing/core'

interface FindIndex {
  <T>(fn: ArrPred<T>, list: ArrayLike<T>): number;
  <T>(fn: ArrPred<T>): (list: ArrayLike<T>) => number;
}

// Returns the index of the first element of the list which matches the predicate, or `-1` if no element matches.
export const findArrayIndex = curryN(2, <T>(fn: ArrPred<T>, arr: ArrayLike<T> = []) => {
  for (let i = 0; i < arr.length; i++) {
      if (fn(arr[i], i, arr)) {
          return i;
      }
  }

  return -1;
}) as FindIndex