Hello,

I am working on Liquid Haskell, and I'd like to use the unfoldings of definitions located in interface files to unfold them in proofs.

Liquid Haskell is a GHC plugin that runs in the type checking phase at the moment, and for analysis purposes it also compiles the module down to Core. I have found that unfolding information is available in the mi_decls field of ModIface, and in the field realUnfoldingInfo of IdInfo. However, my first attempts to grab for these fields yield no unfoldings either because they have been erased (mi_decls is filled with an error call in loadInterface) or they were not constructed to begin with (realUnfoldingInfo is set to NoUnfolding).

In my setting, I have the name of a function, and I would need to retrieve the unfoldings (if they exist) from some environment. Does this environment exist already that is reachable to a plugin? Or do I need to construct it somehow?

I also found that GHC makes a distinction between interface files in external packages and the home package, while I really would like to get the unfolding from wherever they happen to be. 

Any advice is appreciated.