Use "clear -H" for set_solver.

Also, use "set_solver by tac" to specify a tactic.

barrier/barrier.v

@@ -42,7 +42,7 @@ Module barrier_proto.
   Proof.
     split.
     - move=>[p I]. rewrite /= /tok !mkSet_elem_of /= =>HI.
-      destruct p; set_solver eauto.
+      destruct p; set_solver by eauto.
     - (* If we do the destruct of the states early, and then inversion
          on the proof of a transition, it doesn't work - we do not obtain
          the equalities we need. So we destruct the states late, because this
@@ -90,7 +90,7 @@ Module barrier_proto.
     i ∈ I → sts.steps (State High I, {[ Change i ]}) (State High (I ∖ {[ i ]}), ∅).
   Proof.
     intros. apply rtc_once.
-    constructor; first constructor; rewrite /= /tok /=; [set_solver eauto..|].
+    constructor; first constructor; rewrite /= /tok /=; [set_solver by eauto..|].
     (* TODO this proof is rather annoying. *)
     apply elem_of_equiv=>t. rewrite !elem_of_union.
     rewrite !mkSet_elem_of /change_tokens /=.

prelude/collections.v

@@ -253,19 +253,18 @@ Ltac set_unfold :=
 (** Since [firstorder] fails or loops on very small goals generated by
 [set_solver] already. We use the [naive_solver] tactic as a substitute.
 This tactic either fails or proves the goal. *)
-Tactic Notation "set_solver" tactic3(tac) :=
+Tactic Notation "set_solver" "by" tactic3(tac) :=
   setoid_subst;
   decompose_empty;
   set_unfold;
   naive_solver tac.
-Tactic Notation "set_solver" "-" hyp_list(Hs) "/" tactic3(tac) :=
-  clear Hs; set_solver tac.
-Tactic Notation "set_solver" "+" hyp_list(Hs) "/" tactic3(tac) :=
-  revert Hs; clear; set_solver tac.
-Tactic Notation "set_solver" := set_solver idtac.
+Tactic Notation "set_solver" "-" hyp_list(Hs) "by" tactic3(tac) :=
+  clear Hs; set_solver by tac.
+Tactic Notation "set_solver" "+" hyp_list(Hs) "by" tactic3(tac) :=
+  clear -Hs; set_solver by tac.
+Tactic Notation "set_solver" := set_solver by idtac.
 Tactic Notation "set_solver" "-" hyp_list(Hs) := clear Hs; set_solver.
-Tactic Notation "set_solver" "+" hyp_list(Hs) :=
-  revert Hs; clear; set_solver.
+Tactic Notation "set_solver" "+" hyp_list(Hs) := clear -Hs; set_solver.
 
 (** * More theorems *)
 Section collection.
@@ -537,10 +536,10 @@ Section collection_monad.
 
   Global Instance collection_fmap_mono {A B} :
     Proper (pointwise_relation _ (=) ==> (⊆) ==> (⊆)) (@fmap M _ A B).
-  Proof. intros f g ? X Y ?; set_solver eauto. Qed.
+  Proof. intros f g ? X Y ?; set_solver by eauto. Qed.
   Global Instance collection_fmap_proper {A B} :
     Proper (pointwise_relation _ (=) ==> (≡) ==> (≡)) (@fmap M _ A B).
-  Proof. intros f g ? X Y [??]; split; set_solver eauto. Qed.
+  Proof. intros f g ? X Y [??]; split; set_solver by eauto. Qed.
   Global Instance collection_bind_mono {A B} :
     Proper (((=) ==> (⊆)) ==> (⊆) ==> (⊆)) (@mbind M _ A B).
   Proof. unfold respectful; intros f g Hfg X Y ?; set_solver. Qed.
@@ -575,12 +574,12 @@ Section collection_monad.
     l ∈ mapM f k ↔ Forall2 (λ x y, x ∈ f y) l k.
   Proof.
     split.
-    - revert l. induction k; set_solver eauto.
+    - revert l. induction k; set_solver by eauto.
     - induction 1; set_solver.
   Qed.
   Lemma collection_mapM_length {A B} (f : A → M B) l k :
     l ∈ mapM f k → length l = length k.
-  Proof. revert l; induction k; set_solver eauto. Qed.
+  Proof. revert l; induction k; set_solver by eauto. Qed.
   Lemma elem_of_mapM_fmap {A B} (f : A → B) (g : B → M A) l k :
     Forall (λ x, ∀ y, y ∈ g x → f y = x) l → k ∈ mapM g l → fmap f k = l.
   Proof.