/**
 * Returns a new array, containing all elements in the given array transformed using the given transformer, except the ones
 * that were transformed to `null` or `undefined`
 *
 * Example:
 *
 * ```ts
 * import { mapNotNullish } from "https://deno.land/std@$STD_VERSION/collections/mod.ts";
 * import { assertEquals } from "https://deno.land/std@$STD_VERSION/testing/asserts.ts";
 *
 * const people = [
 *     { middleName: null },
 *     { middleName: 'William' },
 *     { middleName: undefined },
 *     { middleName: 'Martha' },
 * ]
 * const foundMiddleNames = mapNotNullish(people, it => it.middleName)
 *
 * assertEquals(foundMiddleNames, [ 'William', 'Martha' ])
 * ```
 */
export declare function mapNotNullish<T, O>(array: readonly T[], transformer: (el: T) => O): NonNullable<O>[];