Rawan programmeercursus

Main.purs

module Main where

import Prelude

import Control.Monad.Eff.Console (logShow, log)
import Data.Tuple
import Data.Map (Map, lookup, singleton)
import TryPureScript

main = render =<< withConsole do
  log "Rawan"
  logShow (fst t1)
  logShow (sec t1)

  logShow (vat 100.0)
  logShow (vat 200.0)
  
  logShow (canDrink 17)
  logShow (canDrink 21)

  logShow (drinkyDrinky (canDrink 17))
  logShow (drinkyDrinky (canDrink 21))

  (logShow <<< drinkyDrinky <<< canDrink) 17
  (logShow <<< drinkyDrinky <<< canDrink) 21
  
  logShow true
  logShow false
  logShow (not true)
  logShow (not false)
  
  logShow (true && false)
  logShow (true && true)
  logShow (not false)
  logShow (true && not true)

  logShow  (rl SweetSour)
  logShow  (rl2 Vinegar SweetSour)

  log ("hoi Rawan: " <> show (Vinegar == Vinegar))

  log "--- hier komen de smaakjes weer -------------"
  logShow (rl3 Vinegar Paprika)
  logShow (rl3 Vinegar SweetSour)
  logShow (rl3 SweetSour Paprika)

  log "--- some lambda stuff -------------"
  logShow (f1 42)          -- applying a named lambda (= lambda function, anonymous function)
  logShow ((\x -> x+1) 41) -- applying an anonymous (inline) lambda
  logShow (f2 3 4)         -- applying a named lambda taking 2 parameters
  
-----------------------------------------------------------------

-- the backslash (\) is meant to look like a lowercase lambda
f1 :: Int -> Int
f1 = \x -> x+1

-- the backslash (\) is meant to look like a lowercase lambda
f2 :: Int -> Int -> Int
f2 = \x y -> x + y

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

drinkyDrinky :: Boolean -> String
drinkyDrinky true  = "here ye are lass!"
drinkyDrinky false = "feck off!"

drinkyDrinky' :: Boolean -> String
drinkyDrinky' = case _ of
  true  -> "here ye are lass!"
  false -> "feck off!"

canDrink :: Int -> Boolean 
canDrink age = age >= 18

vat :: Number -> Number
vat x = x * 0.21

data Flavour = Vinegar | Paprika | SweetSour 

derive instance eqFalvour :: Eq Flavour

rl :: Flavour -> Boolean
rl Vinegar   = true
rl Paprika   = true
rl SweetSour = false

rl2 :: Flavour -> Flavour -> Boolean
rl2 Vinegar   _ = true
rl2 Paprika   _ = true
rl2 SweetSour _ = false

rl3 :: Flavour -> Flavour -> Boolean
--rl3    f1         f2       = rl f1 && rl f2
rl3    f1         f2       = rl f1 `and` rl f2

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

and :: Boolean -> Boolean -> Boolean
and false false = false
and false true  = false
and true  false = false
and true  true  = true

-- rl3    Paprika    Paprika  = true
-- rl3    _          _        = true
-- rl3    f1         f2       = if f1 == Vinegar then true else false
-- rl3    f1         f2       = if f1 ==              true else false

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

t1 = Tuple 'a' 3

-- sec :: Tuple Char Int -> Int
sec :: forall a b. Tuple a b -> b
sec = snd