c10e4c2256
This PR adds a feature to the the mutual def elaborator where the `instance` command yields theorems instead of definitions when the class is a `Prop`. Closes #5672
27 lines
382 B
Text
27 lines
382 B
Text
/-!
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# `instance` creates a theorem if the class is a `Prop`
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https://github.com/leanprover/lean4/issues/5672
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-/
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class A : Prop
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instance a : A where
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/--
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info: theorem a : A :=
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{ }
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-/
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#guard_msgs in #print a
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/-!
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Uses `def` variable inclusion rules
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-/
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section
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variable (x : Nat)
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instance b : A := by
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cases x <;> exact {}
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/-- info: b (x : Nat) : A -/
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#guard_msgs in #check b
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end
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