lean4-htt/old_tests/tests/lean/run/eq9.lean
2018-04-10 12:56:55 -07:00

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Text

open nat
attribute [pattern] lt.base
attribute [pattern] lt.step
theorem lt_succ {a : nat} : ∀ {b : nat}, a < b → succ a < succ b
| .(succ a) (lt.base .(a)) := lt.base (succ a)
| .(succ b) (@lt.step .(a) b h) := lt.step (lt_succ h)