ctxtPlus :: (?globals :: Globals) => Span -> Ctxt Assumption -> Ctxt Assumption
  -> Checker (Ctxt Assumption)
ctxtPlus _ [] ctxt2 = return ctxt2
ctxtPlus :: (?globals :: Globals) => Span -> Ctxt Assumption -> Ctxt Assumption
  -> Checker (Ctxt Assumption)
ctxtPlus _ [] ctxt2 = return ctxt2
ctxtPlus _ [] ctxt2 = return ctxt2