------------ Unfolding  --------------
tidyUnfolding :: TidyEnv -> Unfolding -> Unfolding -> Unfolding
tidyUnfolding tidy_env df@(DFunUnfolding { df_bndrs = bndrs, df_args = args }) _
  = df { df_bndrs = bndrs', df_args = map (tidyExpr tidy_env') args }
  where
    (tidy_env', bndrs') = tidyBndrs tidy_env bndrs
tidyUnfolding :: TidyEnv -> Unfolding -> Unfolding -> Unfolding
tidyUnfolding tidy_env df@(DFunUnfolding { df_bndrs = bndrs, df_args = args }) _
  = df { df_bndrs = bndrs', df_args = map (tidyExpr tidy_env') args }
  where
    (tidy_env', bndrs') = tidyBndrs tidy_env bndrs
tidyUnfolding tidy_env df@(DFunUnfolding { df_bndrs = bndrs, df_args = args }) _
  = df { df_bndrs = bndrs', df_args = map (tidyExpr tidy_env') args }
  where
    (tidy_env', bndrs') = tidyBndrs tidy_env bndrs