13 lines
302 B
Text
13 lines
302 B
Text
/- Simplifier -/
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def mk_symm (xs : List α) :=
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xs ++ xs.reverse
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@[simp] theorem reverse_mk_symm : (mk_symm xs).reverse = mk_symm xs := by
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simp [mk_symm]
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theorem tst : (xs ++ mk_symm ys).reverse = mk_symm ys ++ xs.reverse := by
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simp
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#print tst
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-- Lean reverse_mk_symm, and List.reverse_append
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