Hours of hacking await!
If I break, you can:
  1. Restart:           M-x haskell-process-restart
  2. Configure logging: C-h v haskell-process-log (useful for debugging)
  3. General config:    M-x customize-mode
  4. Hide these tips:   C-h v haskell-process-show-debug-tips
Changed directory: /home/trifon/fmisync/Courses/2019_20/FP_2019_20/sandbox/lectures/haskell/
λ> f (0, "abc", 1)
"abc"
λ> f (0, 3.5, 1)
3.5
λ> :t f
f :: (Eq a1, Eq a2, Num a1, Num a2) => (a1, b, a2) -> b
λ> f (1, 4, 1)
*** Exception: /home/trifon/fmisync/Courses/2019_20/FP_2019_20/sandbox/lectures/haskell/Tuples.hs:3:1-15: Non-exhaustive patterns in function f

λ> h 5 10
15
λ> (((10)))
10
λ> (1,2,3,4)
(1,2,3,4)
λ> [1]:[[]]
[[1],[]]
λ> ""
""
λ> :t ""
"" :: [Char]
λ> :t []
[] :: [a]
λ> 'a':""
"a"
λ> 'a':[]
"a"
λ> length [1,2,3,4,5]
5
λ> null [1,2,3,4,5]
False
λ> tail [1,2,3,4,5]
[2,3,4,5]
λ> length [1,2,3,4,5]
5
λ> :t enumFromTo
enumFromTo :: Enum a => a -> a -> [a]
λ> :t enumFromTo
enumFromTo :: (Ord a, Num a) => a -> a -> [a]
λ> enumFromTo 1 10
[1,2,3,4,5,6,7,8,9,10]
λ> enumFromThenTo 1 3 10
[1,3,5,7,9]
λ> enumFromThenTo 1 3 10
[1,3,5,7,9]
λ> enumFromTo 1 10
[1,2,3,4,5,6,7,8,9,10]
λ> enumFromThenTo 1 3 10
[1,3,5,7,9]
λ> sum [1..10]
55
λ> enumFromThenTo 1 10 3
[1]
λ> [1, 10 .. 3]
[1]
λ> [1 .. -5]
[]
λ> [1,0 .. -5]
[1,0,-1,-2,-3,-4,-5]
λ> [1,0 .. 3]
[]
λ> [1..3] ++ [5..7]
[1,2,3,5,6,7]
λ> reverse [1..5]
[5,4,3,2,1]
λ> reverse [1..5]
[5,4,3,2,1]
λ> [1..10] !! 3
4
λ> [1..10] !! 12
*** Exception: /home/trifon/fmisync/Courses/2019_20/FP_2019_20/sandbox/lectures/haskell/Lists.hs:(53,1)-(54,25): Non-exhaustive patterns in function !!

λ> [1..10] !! 12
*** Exception: Опит за извличане на елемент от празен списък
CallStack (from HasCallStack):
  error, called at /home/trifon/fmisync/Courses/2019_20/FP_2019_20/sandbox/lectures/haskell/Lists.hs:53:14 in main:Lists
λ> [1..10] !! (-3)
*** Exception: Опит за извличане на елемент от празен списък
CallStack (from HasCallStack):
  error, called at /home/trifon/fmisync/Courses/2019_20/FP_2019_20/sandbox/lectures/haskell/Lists.hs:53:14 in main:Lists
λ> elem 3 [1..10]
True
λ> elem 13 [1..10]
False
λ> 3 `elem` [1..10]
True
λ> :t length
length :: Num p => [a] -> p
λ> :t Lists.length
Lists.length :: Num p => [a] -> p
λ> :t Lists.length
Lists.length :: [a] -> Int
λ> dropWhile odd [1,3,4,5,6]
\[4,5,6]
λ> any odd [1..10]
True
λ> any (<0) [1..10]
False
λ> zip [1..10] [2..10]
[(1,2),(2,3),(3,4),(4,5),(5,6),(6,7),(7,8),(8,9),(9,10)]
λ>