Accessing the "original" names via GHC API

24 Jan 2017

      Hi,

I'm quite vexed trying to do the following. Suppose I have a file:

```
module Foo

import qualified Data.Set as S

baz :: S.Set Int
baz = S.empty
```

My goal is to write a function

   tyconString :: TyCon -> String

(perhaps with extra parameters) such that given the
`TyCon` corresponding to `Set`, I get back the "original"
name `S.Set`, or even `Data.Set.Set`.

Everything I've tried, which is fiddling with different variants of
`PprStyle`, end up giving me `Data.Set.Base.Set`

Does anyone have a suggestion for how to proceed?

Thanks!

- Ranjit.

Ranjit Jhala