Incorporated review comments from #1193

exercises/practice/rational-numbers/.meta/examples/success-standard/src/RationalNumbers.hs

@@ -1,13 +1,15 @@
 module RationalNumbers
 (Rational,
  abs,
- reduce,
+ numerator,
+ denominator,
  add,
  sub,
  mul,
  div,
- exprational,
- expreal,
+ pow,
+ expRational,
+ expReal,
  rational) where
 
 import Prelude hiding (div, abs, Rational)
@@ -16,35 +18,40 @@ import qualified Prelude as P
 -- Data definition -------------------------------------------------------------
 data Rational a = Rational a a deriving(Eq, Show)
 
-rational :: (a, a) -> Rational a
-rational (n, d) = Rational n d
+rational :: Integral a => (a, a) -> Rational a
+rational (n, d) = Rational (n' `quot` g) (d' `quot` g)
+    where
+        g = gcd n d
+        (n', d') = if d < 0 then (-n, -d) else (n, d)
 
 -- unary operators -------------------------------------------------------------
 abs :: Integral a => Rational a -> Rational a
-abs (Rational n d ) = reduce $ Rational (P.abs n) (P.abs d)
+abs (Rational n d) = rational (P.abs n, P.abs d)
 
-reduce :: Integral a => Rational a -> Rational a
-reduce (Rational n d) = Rational (n' `quot` g) (d' `quot` g)
-    where
-        g = gcd n d
-        (n', d') = if d < 0 then (-n, -d) else (n, d)
+numerator :: Integral a => Rational a -> a
+numerator (Rational n _) = n
 
+denominator :: Integral a => Rational a -> a
+denominator (Rational _ d) = d
 
 -- binary operators ------------------------------------------------------------
 add :: Integral a => Rational a -> Rational a -> Rational a
-add (Rational n1 d1) (Rational n2 d2) = let dd = d1*d2 in reduce $ Rational (n1*d2 + n2*d1) dd
+add (Rational n1 d1) (Rational n2 d2) = let dd = d1*d2 in rational (n1*d2 + n2*d1, dd)
 
 sub :: Integral a => Rational a -> Rational a -> Rational a
-sub (Rational n1 d1) (Rational n2 d2) = let dd = d1*d2 in reduce $ Rational (n1*d2 - n2*d1) dd
+sub (Rational n1 d1) (Rational n2 d2) = let dd = d1*d2 in rational (n1*d2 - n2*d1, dd)
 
 mul :: Integral a => Rational a -> Rational a -> Rational a
-mul (Rational n1 d1) (Rational n2 d2) = reduce $ Rational (n1*n2) (d1*d2)
+mul (Rational n1 d1) (Rational n2 d2) = rational (n1*n2, d1*d2)
 
 div :: Integral a => Rational a -> Rational a -> Rational a
-div (Rational n1 d1) (Rational n2 d2) = reduce $ Rational (n1*d2) (d1*n2)
+div (Rational n1 d1) (Rational n2 d2) = rational (n1*d2, d1*n2)
+
+pow :: Integral a => Rational a -> a -> Rational a
+pow (Rational n d) num = if num >= 0 then rational (n^num, d^num) else rational (d^(-num), n^(-num))
 
-exprational :: Integral a => Rational a -> a -> Rational a
-exprational (Rational n d) num = reduce $ if num >= 0 then Rational (n^num) (d^num) else Rational (d^(-num)) (n^(-num))
+expRational :: Integral a => Floating b => Rational a -> b -> b
+expRational (Rational n d) num = (fromIntegral n / fromIntegral d) ** num
 
-expreal :: Floating a => Integral b => a -> Rational b -> a
-expreal num (Rational n d) = num ** (fromIntegral n / fromIntegral d)
+expReal :: Floating a => Integral b => a -> Rational b -> a
+expReal num (Rational n d) = num ** (fromIntegral n / fromIntegral d)

exercises/practice/rational-numbers/src/RationalNumbers.hs

@@ -1,29 +1,34 @@
 module RationalNumbers
 (Rational,
  abs,
- reduce,
+ numerator,
+ denominator,
  add,
  sub,
  mul,
  div,
- exprational,
- expreal,
+ pow,
+ expRational,
+ expReal,
  rational) where
 
 import Prelude hiding (div, abs, Rational)
 
 -- Data definition -------------------------------------------------------------
 data Rational a = Dummy deriving(Eq, Show)
 
-rational :: (a, a) -> Rational a
+rational :: Integral a => (a, a) -> Rational a
 rational = error "You need to implement this function"
 
 -- unary operators -------------------------------------------------------------
 abs :: Integral a => Rational a -> Rational a
 abs = error "You need to implement this function"
 
-reduce :: Integral a => Rational a -> Rational a
-reduce = error "You need to implement this function"
+numerator :: Integral a => Rational a -> a
+numerator = error "You need to implement this function"
+
+denominator :: Integral a => Rational a -> a
+denominator = error "You need to implement this function"
 
 -- binary operators ------------------------------------------------------------
 add :: Integral a => Rational a -> Rational a -> Rational a
@@ -38,9 +43,11 @@ mul = error "You need to implement this function"
 div :: Integral a => Rational a -> Rational a -> Rational a
 div = error "You need to implement this function"
 
-exprational :: Integral a => Rational a -> a -> Rational a
-exprational = error "You need to implement this function"
+pow :: Integral a => Rational a -> a -> Rational a
+pow = error "You need to implement this function"
 
-expreal :: Floating a => Integral b => a -> Rational b -> a
-expreal = error "You need to implement this function"
+expRational :: Integral a => Floating b => Rational a -> b -> b
+expRational = error "You need to implement this function"
 
+expReal :: Floating a => Integral b => a -> Rational b -> a
+expReal = error "You need to implement this function"