Call Arity, oneShot or both

[Simon Peyton Jones]

| > Serialising the one-shot lambda info sounds like a good plan to me.
| 
| Ok, thanks for guidance. Is
| https://ghc.haskell.org/trac/ghc/wiki/OneShot#PreservationofsetOneShotLam
| bdaacrossmoduleboundaries
| a sensible design?

Generally yes, but I'd define a new data IfaceLamBndr, rather like IfaceLetBndr, rather than clutter up IfaceLam itself. 

Simon