20 lines
491 B
Text
20 lines
491 B
Text
example : True := by
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if 1 + 1 = 2 then _ else ?_
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case pos => trivial
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fail_if_success case neg => contradiction
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· contradiction
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example (p : Prop) : True := by
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if p then ?foo else trivial
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case foo => trivial
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/-! Should not accidentally leak `open Classical` into branches. -/
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/--
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error: failed to synthesize
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Decidable p
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use `set_option diagnostics true` to get diagnostic information
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-/
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#guard_msgs in
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example (p : Prop) : True := by
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if p then exact decide p else trivial
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