rustc/infer: readability improvements

Author: ljedrz

src/librustc/infer/canonical/query_result.rs

@@ -499,24 +499,22 @@ impl<'cx, 'gcx, 'tcx> InferCtxt<'cx, 'gcx, 'tcx> {
                     let ty::OutlivesPredicate(k1, r2) = constraint.skip_binder(); // restored below
                     let k1 = substitute_value(self.tcx, result_subst, k1);
                     let r2 = substitute_value(self.tcx, result_subst, r2);
-                    match k1.unpack() {
-                        UnpackedKind::Lifetime(r1) => Obligation::new(
-                            cause.clone(),
-                            param_env,
-                            ty::Predicate::RegionOutlives(ty::Binder::dummy(
-                                ty::OutlivesPredicate(r1, r2),
-                            )),
-                        ),
 
-                        UnpackedKind::Type(t1) => Obligation::new(
+                    Obligation::new(
                         cause.clone(),
                         param_env,
-                            ty::Predicate::TypeOutlives(ty::Binder::dummy(ty::OutlivesPredicate(
-                                t1, r2,
-                            ))),
-                        ),
+                        match k1.unpack() {
+                            UnpackedKind::Lifetime(r1) => ty::Predicate::RegionOutlives(
+                                ty::Binder::dummy(
+                                    ty::OutlivesPredicate(r1, r2)
+                            )),
+                            UnpackedKind::Type(t1) => ty::Predicate::TypeOutlives(
+                                ty::Binder::dummy(ty::OutlivesPredicate(
+                                    t1, r2
+                            )))
                         }
-                }),
+                    )
+                })
         ) as Box<dyn Iterator<Item = _>>
     }
 

src/librustc/infer/equate.rs

@@ -77,24 +77,22 @@ impl<'combine, 'infcx, 'gcx, 'tcx> TypeRelation<'infcx, 'gcx, 'tcx>
         match (&a.sty, &b.sty) {
             (&ty::Infer(TyVar(a_id)), &ty::Infer(TyVar(b_id))) => {
                 infcx.type_variables.borrow_mut().equate(a_id, b_id);
-                Ok(a)
             }
 
             (&ty::Infer(TyVar(a_id)), _) => {
                 self.fields.instantiate(b, RelationDir::EqTo, a_id, self.a_is_expected)?;
-                Ok(a)
             }
 
             (_, &ty::Infer(TyVar(b_id))) => {
                 self.fields.instantiate(a, RelationDir::EqTo, b_id, self.a_is_expected)?;
-                Ok(a)
             }
 
             _ => {
                 self.fields.infcx.super_combine_tys(self, a, b)?;
-                Ok(a)
             }
         }
+
+        Ok(a)
     }
 
     fn regions(&mut self, a: ty::Region<'tcx>, b: ty::Region<'tcx>)