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haskell - write haskell modules and load/import in ghci

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You may want to write up some haskell modules and put it into the interactive ghci command prompt so that you can see how it works out... it is more  a repl things.

suppose that you have write the following modules.

-- file:
--   Person.hs
-- description:
--   the file defines the Person object

module Person
( Person(..)
, firstName
, lastName
, age
, height
, phoneNumber
, flavor
) where

data Person = Person String String Int Float String String deriving (Show)

firstName :: Person -> String
firstName (Person firstName _ _ _ _ _) = firstName

lastName :: Person -> String
lastName (Person _ lastName _ _ _ _) = lastName

age :: Person -> Int
age (Person _ _ age _ _ _ ) = age

height :: Person -> Float
height (Person _ _ _ height _ _) = height

phoneNumber :: Person -> String
phoneNumber (Person _ _ _ _ number _) = number

flavor :: Person -> String
flavor (Person _ _ _ _ _ flavor) = flavor

--
-- alternative way to write data types
-- with mnemonic such as follo
-- NOTE :
--  Check on the Person2.hs

 

And from the haskell command window, you may do the following

 

Prelude> :l Person.hs
[1 of 1] Compiling Person           ( Person.hs, interpreted )
Ok, modules loaded: Person.
*Person> import Person

 That is basically , first load up the file and secondly try to do the import things.

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