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type Partition = {  <T, S extends T>(list: T[], predicate: (el: T) => el is S): [    S[],    Exclude<T, S>[],  ];  <T extends readonly unknown[], S>(    list: T,    predicate: (el: any) => el is S,  ): Part<T, S>;  <T>(list: T[], predicate: (el: T) => unknown): [T[], T[]];};
/** * Takes a `list` and returns a pair of lists containing: the elements that * match the `predicate` and those that don't, respectively. * * Think of it as `filter`, but the elements that don't pass the filter aren't * discarded but returned in a separate list instead. * * @example * ``` * const [strings, numbers] = partition( *   ['a', 'b', 1, 'c', 2, 3], *   (el): el is string => typeof el === 'string' * ) * // strings: ["a", "b", "c"] * // numbers: [1, 2, 3] * ``` */const partition: Partition = <T>(list: T[], predicate: (el: T) => unknown) =>  list.reduce(    ([t, f], c) => (predicate(c) ? [[...t, c], f] : [t, [...f, c]]) as any,    [[], []],  ) as any;
export default partition;
type Part<T extends readonly unknown[], S> = T extends readonly [  infer F,  ...infer R,] ? [    F extends S ? [F, ...Part<R, S>[0]] : Part<R, S>[0],    F extends S ? Part<R, S>[1] : [F, ...Part<R, S>[1]],  ]  : [[], []];