No way to import a data instance

import Foreign.R.Type as R (SComplex)

results in

    In module ‘Foreign.R.Type’:
      ‘SComplex’ is a data constructor of ‘Sing’
    To import it use
      ‘import’ Foreign.R.Type( Sing( SComplex ) )
    or
      ‘import’ Foreign.R.Type( Sing(..) )

But if I try the suggested

import Foreign.R.Type as R (Sing(SComplex))

I get

    Module ‘Foreign.R.Type’ does not export ‘Sing(SComplex)’

So, when a module defines a data instance but does not export the family, there appears to be no way to bring that instance in scope (short of importing the whole module).

Here's the module itself http://haddock.stackage.org/nightly-2015-10-19/inline-r-0.7.1.2/Foreign-R-Type.html. It doesn't have an explicit export list; that's how it manages to export instances without the family itself.

Trac metadata

Trac field	Value
Version	7.10.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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