'use strict' const ageGroup = { BABY: 'B', CHILD: 'K', YOUNG: 'Y', ADULT: 'E', SENIOR: 'S', upperBoundOf: { BABY: 6, CHILD: 15, YOUNG: 27, ADULT: 65, SENIOR: Infinity } } const ageGroupFromAge = (age) => { const {upperBoundOf} = ageGroup if (age < upperBoundOf.BABY) return ageGroup.BABY if (age < upperBoundOf.CHILD) return ageGroup.CHILD if (age < upperBoundOf.YOUNG) return ageGroup.YOUNG if (age < upperBoundOf.ADULT) return ageGroup.ADULT if (age < upperBoundOf.SENIOR) return ageGroup.SENIOR throw new TypeError(`Invalid age '${age}'`) } module.exports = { ageGroup, ageGroupFromAge }