13 lines
296 B
Text
13 lines
296 B
Text
--
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open nat tactic
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example (a b : nat) : a = succ b → a = b + 1 :=
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by do
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H ← intro `H,
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try (dunfold_at [`nat.succ] H),
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dunfold [`add, `has_add.add, `has_one.one, `nat.add, `one],
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trace_state,
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t ← target,
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expected ← to_expr `(a = succ b),
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guard (t = expected),
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assumption
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