Make iPure and iPersistent internal to reduce the number of tactics.

These tactics are superfluous:
- iPure H as pat => iDestruct H as pat
- iPersistent H => iSpecialize H "!"

heap_lang/lib/barrier/proof.v

@@ -176,7 +176,7 @@ Proof.
   iSts γ as [p I]; iDestruct "Hγ" as "[Hl Hr]".
   iPvs (saved_prop_alloc_strong _ (R1: ∙%CF iProp) I) as {i1} "[% #Hi1]".
   iPvs (saved_prop_alloc_strong _ (R2: ∙%CF iProp) (I ∪ {[i1]}))
-    as {i2} "[Hi2' #Hi2]"; iPure "Hi2'" as Hi2; iPvsIntro.
+    as {i2} "[Hi2' #Hi2]"; iDestruct "Hi2'" as %Hi2; iPvsIntro.
   rewrite ->not_elem_of_union, elem_of_singleton in Hi2; destruct Hi2.
   iExists (State p ({[i1]} ∪ ({[i2]} ∪ (I ∖ {[i]})))).
   iExists ({[Change i1 ]} ∪ {[ Change i2 ]}).

program_logic/hoare_lifting.v

@@ -57,8 +57,8 @@ Proof.
   repeat iSplit.
   - by iApply vs_reflexive.
   - iIntros {e2 σ2 ef} "! (#Hφ&Hown&HP)"; iPvsIntro.
-    iSplitL "Hown". by iSplit. iSplit. by iPure "Hφ" as [_ ?]. done.
-  - iIntros {e2 σ2 ef} "! [Hown #Hφ]"; iPure "Hφ" as [[v2 <-%of_to_val] ?].
+    iSplitL "Hown". by iSplit. iSplit. by iDestruct "Hφ" as %[_ ?]. done.
+  - iIntros {e2 σ2 ef} "! [Hown #Hφ]"; iDestruct "Hφ" as %[[v2 <-%of_to_val] ?].
     iApply wp_value'. iExists σ2, ef. by iSplit.
   - done.
 Qed.
@@ -89,8 +89,8 @@ Proof.
   iIntros {? Hsafe Hdet} "[#He2 #Hef]".
   iApply (ht_lift_pure_step _ (λ e2' ef', e2 = e2' ∧ ef = ef')); eauto.
   iSplit; iIntros {e2' ef'}.
-  - iIntros "! [#He ?]"; iPure "He" as [-> ->]. by iApply "He2".
+  - iIntros "! [#He ?]"; iDestruct "He" as %[-> ->]. by iApply "He2".
   - destruct ef' as [e'|]; last done.
-    iIntros "! [#He ?]"; iPure "He" as [-> ->]. by iApply "Hef" "!".
+    iIntros "! [#He ?]"; iDestruct "He" as %[-> ->]. by iApply "Hef" "!".
 Qed.
 End lifting.

proofmode/tactics.v

@@ -138,7 +138,7 @@ Local Tactic Notation "iIntro" "#" constr(H) :=
   end.
 
 (** * Making hypotheses persistent or pure *)
-Tactic Notation "iPersistent" constr(H) :=
+Local Tactic Notation "iPersistent" constr(H) :=
   eapply tac_persistent with _ H _ _ _; (* (i:=H) *)
     [env_cbv; reflexivity || fail "iPersistent:" H "not found"
     |let Q := match goal with |- ToPersistentP ?Q _ => Q end in
@@ -153,13 +153,12 @@ Tactic Notation "iDuplicate" constr(H1) "as" constr(H2) :=
 Tactic Notation "iDuplicate" "#" constr(H1) "as" constr(H2) :=
   iPersistent H1; iDuplicate H1 as H2.
 
-Tactic Notation "iPure" constr(H) "as" simple_intropattern(pat) :=
+Local Tactic Notation "iPure" constr(H) "as" simple_intropattern(pat) :=
   eapply tac_pure with _ H _ _ _; (* (i:=H1) *)
     [env_cbv; reflexivity || fail "iPure:" H "not found"
     |let P := match goal with |- ToPure ?P _ => P end in
      apply _ || fail "iPure:" H ":" P "not pure"
     |intros pat].
-Tactic Notation "iPure" constr(H) := iPure H as ?.
 
 Tactic Notation "iPureIntro" := apply uPred.const_intro.
 
@@ -544,7 +543,7 @@ Local Tactic Notation "iDestructHyp" constr(H) "as" constr(pat) :=
   let rec go Hz pat :=
     lazymatch pat with
     | IAnom => idtac
-    | IAnomPure => iPure Hz
+    | IAnomPure => iPure Hz as ?
     | IDrop => iClear Hz
     | IFrame => iFrame Hz
     | IName ?y => iRename Hz into y