973b.lean:5:8-5:10: warning: declaration uses 'sorry'
973b.lean:9:8-9:11: warning: declaration uses 'sorry'
[Meta.Tactic.simp.discharge] >> discharge?: ?p x
[Meta.Tactic.simp.discharge] @ex, failed to discharge hypotheses
      ?p x
[Meta.Tactic.simp.discharge] >> discharge?: ?p (f x)
[Meta.Tactic.simp.discharge] >> discharge?: ?p x
[Meta.Tactic.simp.discharge] @ex, failed to discharge hypotheses
      ?p x
[Meta.Tactic.simp.discharge] >> discharge?: ?p x
[Meta.Tactic.simp.discharge] @ex, failed to discharge hypotheses
      ?p x
[Meta.Tactic.simp.discharge] @ex, failed to discharge hypotheses ?p (f x)