poole@CPSC-M-POOLE01 haskell % ghci
GHCi, version 9.4.8: https://www.haskell.org/ghc/  :? for help
ghci> :l Lists3
[1 of 1] Compiling Lists3           ( Lists3.hs, interpreted )
Ok, one module loaded.
ghci> :type myfoldr (&&)
myfoldr (&&) :: Bool -> [Bool] -> Bool
ghci> myfoldr (\ x y -> 10*x : y) [] [1,2,3,4]
[10,20,30,40]
ghci> myfoldr (\ x y -> 10*x + y) 0 [1,2,3,4]
100
ghci> myfoldr (\ x y -> x + 10*y) 0 [1,2,3,4]
4321

ghci> :l Lists4
[1 of 1] Compiling Lists4           ( Lists4.hs, interpreted )
Ok, one module loaded.
ghci> r2 [1,2] [3,4]
[4,3,1,2]
ghci> rev [1,2,4,6,11,23,45,56]
[56,45,23,11,6,4,2,1]
ghci> myfoldl (+) 0 [1..10]
55
ghci> myfoldl (:) [] [1..10]

<interactive>:12:9: error:
    • Couldn't match type ‘a’ with ‘[a]’
      Expected: [a] -> [[a]] -> [a]
        Actual: [a] -> [[a]] -> [[a]]
      ‘a’ is a rigid type variable bound by
        the inferred type of it :: [a]
        at <interactive>:12:1-22
    • In the first argument of ‘myfoldl’, namely ‘(:)’
      In the expression: myfoldl (:) [] [1 .. 10]
      In an equation for ‘it’: it = myfoldl (:) [] [1 .. 10]
    • Relevant bindings include it :: [a] (bound at <interactive>:12:1)
ghci> myfoldl (flip (:)) [] [1..10]
[10,9,8,7,6,5,4,3,2,1]
ghci> myfoldl consi [] [1..10]
[10,9,8,7,6,5,4,3,2,1]
ghci> :type re
re :: [t] -> [t]
ghci> ch2dig '4'
4
ghci> ch2dig 'e'
53
ghci> myfoldl (\n c -> 10*n + ch2dig c) 0 "1234"
1234
ghci> str2int "-543212345"
-543212345
ghci> :l Lists3
[1 of 1] Compiling Lists3           ( Lists3.hs, interpreted )
Ok, one module loaded.
ghci> :type myfoldr
myfoldr :: (t1 -> t2 -> t2) -> t2 -> [t1] -> t2
ghci> :type myfoldr (&&)
myfoldr (&&) :: Bool -> [Bool] -> Bool
ghci> :type (&&)
(&&) :: Bool -> Bool -> Bool
ghci> :type myfoldr (+)
myfoldr (+) :: Num t2 => t2 -> [t2] -> t2
ghci> a = (+4)
ghci> a 3
7