1 files changed, 25 insertions, 0 deletions
diff --git a/src/Util/Tactics.v b/src/Util/Tactics.v
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+(** * Generic Tactics *)
+
+(* [pose proof defn], but only if no hypothesis of the same type exists.
+   most useful for proofs of a proposition *)
+Tactic Notation "unique" "pose" "proof" constr(defn) :=
+  let T := type of defn in
+  match goal with
+  | [ H : T |- _ ] => fail 1
+  | _ => pose proof defn
+  end.
+(* [assert T], but only if no hypothesis of the same type exists.
+   most useful for proofs of a proposition *)
+Tactic Notation "unique" "assert" constr(T) :=
+  match goal with
+  | [ H : T |- _ ] => fail 1
+  | _ => assert T
+  end.
+
+(* [assert T], but only if no hypothesis of the same type exists.
+   most useful for proofs of a proposition *)
+Tactic Notation "unique" "assert" constr(T) "by" tactic3(tac) :=
+  match goal with
+  | [ H : T |- _ ] => fail 1
+  | _ => assert T by tac
+  end.