unknownTactic.lean:3:3: error: unknown tactic
unknownTactic.lean:1:41-3:8: error: unsolved goals
x : Nat
a✝ : x = x
⊢ x = x
---
unknownTactic.lean:8:22: error: unknown tactic
unknownTactic.lean:8:18-8:24: error: unsolved goals
x : Nat
⊢ x = x
---
unknownTactic.lean:14:22: error: unknown tactic
unknownTactic.lean:14:18-14:24: error: unsolved goals
x : Nat
⊢ x = x