-- The rest are routine
add gp@(HsGroup {hs_instds = ts}) l (InstD d) ds
= addl (gp { hs_instds = L l d : ts }) ds
+add gp@(HsGroup {hs_derivds = ts}) l (DerivD d) ds
+ = addl (gp { hs_derivds = L l d : ts }) ds
add gp@(HsGroup {hs_defds = ts}) l (DefD d) ds
= addl (gp { hs_defds = L l d : ts }) ds
add gp@(HsGroup {hs_fords = ts}) l (ForD d) ds