haskell - How to import specific PortNumber constructor -


simple question.

this compiles:

module example import network port :: portid port = portnumber 3001

and not:

module example import network (portid, portnumber) port :: portid port = portnumber 3001

ghc says:

example.hs:6:8: not in scope: data constructor `portnumber'

why?

it has be

import network (portid(portnumber))

as portnumber seems constructor of portid. other import imports of network , hence portnumber found.


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