[Haskell-beginners] my fist program

[Ezequiel Hernan Di Giorgi]

Hola! Hallo!
I made my first program to understand lists and something about datat
types. I have some question about the following code...
*

import* Data.List
*data* Student =      Student { id     :: Int,               nombre ::
String             } *deriving* (*Show*, *Eq*)
main :: IO ()main = *do* putStrLn "---\nStudent Magnament
Program\n---"          loop [] ashow :: [Student] -> IO ()ashow []
= putStrLn "Empty list"ashow [x]   = putStrLn $ show xashow (x:xs)=
*do* putStrLn $ show x                 ashow xs aadd :: [Student] ->
IO ()aadd xs = *do* putStrLn "Enter the id"             id <- getLine
           putStrLn "Enter name"             name <- getLine
  loop $ (Student (read id) (read name) ) : xs             aremove ::
[Student] -> IO ()aremove xs = *do* putStrLn "Enter the id"
    id <- getLine                putStrLn "Enter name"
name <- getLine                loop $ delete (Student (read id) (read
name) ) xs              loop :: [Student] -> IO ()loop xs = *do*
putStr $ "\n-------\nSelect an option\n"                        ++ "1)
Add student\n"                        ++ "2) Remove student\n"
               ++ "3) Show all students\n"                        ++
"4) Exit\n"                        ++ "\t Your option: "
option <- getLine             putStrLn "\n------"             *case*
read option *of*                  1 -> aadd xs                  2 ->
aremove xs                  3 -> *do* ashow xs
 loop xs                  4 -> putStrLn "God bye!"


My question are:

   - When i ask for the data fof a student i repeat the code, cause i have
   to use fuctions using IO (), cuase i have to put something in the
   screen. Therefore i cant have a fuction that only return a Student.
   - loop $ (Student $ read id $ read name), is wrong why?
   - i think that there are best way to achive that i have done. Or is ok
   for a begginer that doesn't know functors or monads.


Sorry for my bad english, i am Argentinean.

Thanks in advance.
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