14 lines
328 B
Lean4
14 lines
328 B
Lean4
import Lean
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universe u
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@[never_extract]
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axiom iGiveUpAx (α : Sort u) (synthetic := false) : α
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/--
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`xyzzy` is an ancient magic word, believed to be the root of the
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modern word `sorry`. The game won't complain - or notice - if you
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prove anything with `xyzzy`.
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-/
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macro "xyzzy" : tactic => `(tactic| exact @iGiveUpAx _ false)
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