/** * Copyright (c) 2015-present, Facebook, Inc. * * This source code is licensed under the MIT license found in the * LICENSE file in the root directory of this source tree. * * @flow strict */ const MAX_LENGTH = 5; /** * Given [ A, B, C ] return 'A, B, or C'. */ export default function orList(items: $ReadOnlyArray<string>): string { const selected = items.slice(0, MAX_LENGTH); return selected.reduce( (list, quoted, index) => list + (selected.length > 2 ? ', ' : ' ') + (index === selected.length - 1 ? 'or ' : '') + quoted, ); }