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-- user.hs
data UserInfo = UserInfo{
    userId  :: Int
  , name    :: String
} deriving(Show)

relude> :load user.hs
[1 of 1] Compiling Main             ( user.hs, interpreted )
Ok, modules loaded: Main.
*Main> let user = UserInfo 1 "haru01"
*Main> :type userId
userId :: UserInfo -> Int
*Main> userId user
1
*Main> name user
"haru01"
*Main> let user2 = UserInfo { userId = 2, name = "haru02" }
*Main> name user2
"haru02"

"UserInfo { userId = 2, name = "haru02" }"の表記、いいなぁ

Real World Haskell: Code You Can Believe In