Lean.Grind.ToInt.{u} (α : Type u) (range : outParam IntInterval) : Type u
[grind.debug.proof] fun h h_1 h_2 h_3 h_4 h_5 h_6 h_7 h_8 =>
      id
        (let ctx := RArray.branch 1 (RArray.leaf One.one) (RArray.leaf (f 2));
        let p_1 := Poly.nil;
        let p_2 := Poly.add 1 1 Poly.nil;
        let p_3 := Poly.add 1 0 Poly.nil;
        let p_4 := Poly.add (-1) 1 (Poly.add 1 0 Poly.nil);
        let p_5 := Poly.add (-1) 0 Poly.nil;
        let e_1 := (Expr.intMul 1 (Expr.var 1)).add (Expr.intMul 0 (Expr.var 0));
        let e_2 := Expr.zero;
        let e_3 := (Expr.intMul (-1) (Expr.var 1)).add (Expr.intMul 1 (Expr.var 0));
        let rctx := RArray.leaf (f 2);
        let rp_1 := CommRing.Poly.add 1 (CommRing.Mon.mult { x := 0, k := 1 } CommRing.Mon.unit) (CommRing.Poly.num 0);
        let rp_2 :=
          CommRing.Poly.add (-1) (CommRing.Mon.mult { x := 0, k := 1 } CommRing.Mon.unit) (CommRing.Poly.num 1);
        let re_1 := CommRing.Expr.var 0;
        let re_2 := CommRing.Expr.num 0;
        let re_3 := ((CommRing.Expr.num 1).neg.mul (CommRing.Expr.var 0)).add (CommRing.Expr.num 1);
        lt_unsat ctx
          (le_lt_combine ctx p_3 p_5 p_1 (eagerReduce (Eq.refl true))
            (le_le_combine ctx p_4 p_2 p_3 (eagerReduce (Eq.refl true))
              (le_norm ctx e_3 e_2 p_4 (eagerReduce (Eq.refl true))
                (CommRing.le_int_module rctx rp_2
                  (CommRing.le_norm rctx re_3 re_2 rp_2 (eagerReduce (Eq.refl true)) h_8)))
              (le_norm ctx e_1 e_2 p_2 (eagerReduce (Eq.refl true))
                (CommRing.le_int_module rctx rp_1
                  (CommRing.le_norm rctx re_1 re_2 rp_1 (eagerReduce (Eq.refl true)) h_1))))
            (zero_lt_one ctx p_5 (eagerReduce (Eq.refl true)) (Eq.refl One.one))))
Try these:
  [apply] [grind =] for pattern: [r #2 (f #1)]
  [apply] [grind =>] for pattern: [p (f #2), r #2 (f #1)]
  [apply] [grind! =>] for pattern: [f #2, f #1]