fix induction

test/induction.lean

@@ -0,0 +1,28 @@
+import Game.Tactic.Induction
+import Game.MyNat.Addition
+import Mathlib.Tactic.Have
+import Mathlib.Tactic
+
+example (a b : ℕ) : a + b = a → b = 0 := by
+  induction b with d hd
+  -- looks great
+  -- base case
+  /-
+  a : ℕ
+  ⊢ a + 0 = a → 0 = 0
+  -/
+  sorry; sorry
+
+example (a b c : ℕ) (g : c = 0) : a + b = a → b = 0 := by
+  intro h -- h : a + b = a
+  induction b with d hd generalizing g
+  -- aargh
+  -- base case
+  /-
+  a b: ℕ
+  h✝ : a + b = a
+  h : a + 0 = a
+  ⊢ 0 = 0
+  -/
+  -- Why does b still exist in the base case? And why does h✝ exist at all?
+  sorry; sorry