17 lines
390 B
Text
17 lines
390 B
Text
set_option new_elaborator true
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inductive day
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| monday | tuesday | wednesday | thursday | friday | saturday | sunday
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open day
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definition next_weekday : day → day
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| monday := tuesday
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| tuesday := wednesday
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| wednesday := thursday
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| thursday := friday
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| friday := monday
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| saturday := monday
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| sunday := monday
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example : next_weekday (next_weekday monday) = wednesday :=
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rfl
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