diff options
| -rw-r--r-- | _CoqProject | 1 | ||||
| -rw-r--r-- | src/Util/Tactics/HeadUnderBinders.v | 22 |
2 files changed, 23 insertions, 0 deletions
diff --git a/_CoqProject b/_CoqProject index 5e186dcc4..0633c2b00 100644 --- a/_CoqProject +++ b/_CoqProject @@ -4212,6 +4212,7 @@ src/Util/Tactics/EvarExists.v src/Util/Tactics/Forward.v src/Util/Tactics/GetGoal.v src/Util/Tactics/Head.v +src/Util/Tactics/HeadUnderBinders.v src/Util/Tactics/MoveLetIn.v src/Util/Tactics/Not.v src/Util/Tactics/OnSubterms.v diff --git a/src/Util/Tactics/HeadUnderBinders.v b/src/Util/Tactics/HeadUnderBinders.v new file mode 100644 index 000000000..a111a045f --- /dev/null +++ b/src/Util/Tactics/HeadUnderBinders.v @@ -0,0 +1,22 @@ +Require Export Crypto.Util.FixCoqMistakes. + +(** find the head of the given expression, underneath [fun] and [forall] *) +Ltac head_under_binders_gen redtac expr := + let expr := redtac expr in + match expr with + | ?f _ => head_under_binders_gen redtac f + | fun x : ?T => @?f x + => lazymatch constr:(fun x : T + => ltac:(let f' := (eval cbv beta in (f x)) in + let h := head_under_binders_gen redtac f' in + exact h)) with + | fun _ => ?f => f + | ?f => f + end + | forall x, @?f x + => head_under_binders_gen redtac f + | ?expr => expr + end. + +Ltac head_under_binders expr := head_under_binders_gen ltac:(fun e => e) expr. +Ltac head_hnf_under_binders expr := head_under_binders_gen ltac:(fun e => eval hnf in e) expr. |