What does 'qualified' mean in 'import qualified Data.List' statement?

haskell

Solution

A qualified import makes the imported entities available only in qualified form, e.g.

import qualified Data.List

result :: [Int]
result = Data.List.sort [3,1,2,4]

With just `import Data.List`, the entities are available in qualified form and in unqualified form. Usually, just doing a qualified import leads to too long names, so you

import qualified Data.List as L

result :: [Int]
result = L.sort [3,1,2,4]

A qualified import allows using functions with the same name imported from several modules, e.g. `map` from the `Prelude` and `map` from `Data.Map`.

Problem

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