diff options
Diffstat (limited to 'compiler/GHC/Tc/Gen/Rule.hs')
| -rw-r--r-- | compiler/GHC/Tc/Gen/Rule.hs | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/compiler/GHC/Tc/Gen/Rule.hs b/compiler/GHC/Tc/Gen/Rule.hs index 10dffa2648..40e4d55ecf 100644 --- a/compiler/GHC/Tc/Gen/Rule.hs +++ b/compiler/GHC/Tc/Gen/Rule.hs @@ -134,7 +134,7 @@ tcRule (HsRule { rd_ext = ext ; (lhs_evs, residual_lhs_wanted) <- simplifyRule name tc_lvl lhs_wanted rhs_wanted - -- SimplfyRule Plan, step 4 + -- SimplifyRule Plan, step 4 -- Now figure out what to quantify over -- c.f. GHC.Tc.Solver.simplifyInfer -- We quantify over any tyvars free in *either* the rule @@ -306,8 +306,9 @@ revert to SimplCheck when going under an implication. * Step 0: typecheck the LHS and RHS to get constraints from each -* Step 1: Simplify the LHS and RHS constraints all together in one bag - We do this to discover all unification equalities +* Step 1: Simplify the LHS and RHS constraints all together in one bag, + but /discarding/ the simplified constraints. We do this only + to discover all unification equalities. * Step 2: Zonk the ORIGINAL (unsimplified) LHS constraints, to take advantage of those unifications |