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:8:17: error: unknown tactic
unknownTactic.lean:8:2-8:19: error: unsolved goals
x : Nat
⊢ x = x
---
unknownTactic.lean:14:17: error: unknown tactic
unknownTactic.lean:14:2-14:19: error: unsolved goals
x : Nat
⊢ x = x