Haskell. Why does read function does not work with custom data type though I used deriving?

Read function does not work properly with custom data type.

data TwoInts = Int Int
 deriving (Read, Show)

conv :: String -> TwoInts
conv s = read s

When i load this function with ghci ghci conv.hs It loads properly, but when i call it conv "15 14" i am getting following error:

*** Exception: Prelude.read: no parse

As suggested, your data type:

data TwoInts = Int Int
 deriving (Read, Show)

describes a constructor named Int that accepts a type Int. If you were to use records, maybe this is more clear:

data TwoInts = Int { int :: Int}
 deriving (Read, Show)

The solution as suggested in the comments is to name your constructor something else, e.g.,

data TwoInts = TwoInts Int Int
 deriving (Read, Show)

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