// ============= Test Cases =============
import type { Equal, Expect } from './test-utils'

type A1 = FilterOut<[], never>;
type B1 = [];
type C1 = Expect<Equal<A1, B1>>;

type A2 = FilterOut<[never], never>;
type B2 = [];
type C2 = Expect<Equal<A2, B2>>;

type A3 = FilterOut<['a', never], never>;
type B3 = ['a'];
type C3 = Expect<Equal<A3, B3>>;

type A4 = FilterOut<[1, never, 'a'], never>;
type B4 = [1, 'a'];
type C4 = Expect<Equal<A4, B4>>;

type A5 = FilterOut<
  [never, 1, 'a', undefined, false, null],
  never | null | undefined
>;
type B5 = [1, 'a', false];
type C5 = Expect<Equal<A5, B5>>;

type A6 = FilterOut<
  [number | null | undefined, never],
  never | null | undefined
>;
type B6 = [number | null | undefined];
type C6 = Expect<Equal<A6, B6>>;

// ============= Your Code Here =============
type FilterOut<T, Pred> =
  T extends [infer Head, ...infer Tail]
  ? [Head] extends [Pred]
    ? FilterOut<Tail, Pred>
    : [Head, ...FilterOut<Tail, Pred>]
  : [];

// @uid11
type FilterOut<T, Pred> =
  T extends [] // `can skip this whole section`
  ? []
  : T extends [infer Head, ...infer Tail]
    ? [Head] extends [Pred]
      ? FilterOut<Tail, Pred>
      : [Head, ...FilterOut<Tail, Pred>]
    : unknown[] // can remove `unknown`