runTacticMustCatchExceptions.lean:2:25-2:28: error: tactic 'rfl' failed, equality expected
  Nat.le 1 (a + b)
a b : Nat
⊢ 1 ≤ a + b
runTacticMustCatchExceptions.lean:3:25-3:28: error: tactic 'rfl' failed, equality expected
  Nat.le (a + b) b
a b : Nat
this : 1 ≤ a + b
⊢ a + b ≤ b
runTacticMustCatchExceptions.lean:4:25-4:28: error: tactic 'rfl' failed, equality expected
  Nat.le b 2
a b : Nat
: 1 ≤ a + b
this : a + b ≤ b
⊢ b ≤ 2
runTacticMustCatchExceptions.lean:9:18-9:21: error: tactic 'rfl' failed, equality expected
  Nat.le 1 (a + b)
a b : Nat
⊢ 1 ≤ a + b
runTacticMustCatchExceptions.lean:10:14-10:17: error: tactic 'rfl' failed, equality expected
  Nat.le (a + b) b
a b : Nat
⊢ a + b ≤ b
runTacticMustCatchExceptions.lean:11:14-11:17: error: tactic 'rfl' failed, equality expected
  Nat.le b 2
a b : Nat
⊢ b ≤ 2