In Haskell, Solve the Undefined Fraction Function:

------------------------------------------------------------------------

module Fraction (Fraction, frac) where

-- Fraction type. ADT maintains the INVARIANT that every fraction Frac n m

-- satisfies m > 0 and gcd n m == 1. For fractions satisfying this invariant

-- equality is the same as literal equality (hence "deriving Eq")

data Fraction = Frac Integer Integer deriving Eq

-- Public constructor: take two integers, n and m, and construct a fraction

-- representing n/m that satisfies the invariant, if possible

------------------------------------------------------------------------

frac :: Integer -> Integer -> Maybe Fraction

frac = undefined

-- Show instance that outputs Frac n m as n/m

-- Ord instance for Fraction

-- Num instance for Fraction