(Haskell-Book-Chp-11-Task-1)

Chp11.hs

-- Exercise given data types

data OperatingSystem = GnuPlusLinux
                     | OpenBSDPlusNevermindJustBSDStill
                     | Mac
                     | Windows
                     deriving (Eq, Show, Enum)
                     
data ProgrammingLanguage = Haskell
                         | Agda
                         | Idris
                         | PureScript 
                         deriving (Eq, Show, Enum)
                         
data Programmer = Programmer { os :: OperatingSystem
                             , lang :: ProgrammingLanguage }
                  deriving (Eq, Show)
                  
allOperatingSystem :: [OperatingSystem]
allOperatingSystem = [ GnuPlusLinux
                     , OpenBSDPlusNevermindJustBSDStill
                     , Mac
                     , Windows
                     ]
                     
allLanguages :: [ProgrammingLanguage]
allLanguages = [Haskell, Agda, Idris, PureScript]

-- Task:
-- Write allProgrammers functions which will return all possible Programmers 
-- that are working on each OperatingSystem and in each Programming Language.

-- Todays Solution
allProgrammers :: [Programmer]
allProgrammers = (uncurry Programmer) <$> ((,) <$> allOperatingSystem <*> allLanguages)