17f8231d59
This feature is needed when we declare an inductive predicate/type which is indexed by a mutual and/or nested inductive datatype. See tests/lean/run/term_pred.lean for an example. @Armael: this commit should fix the issue with the `cases` tactic that you reported today.
25 lines
599 B
Text
25 lines
599 B
Text
inductive term
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| app : string → list term → term
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| var : string → term
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inductive bin_only : term → Prop
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| leaf : ∀ x, bin_only (term.var x)
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| bin_app : ∀ op a b, bin_only a → bin_only b → bin_only (term.app op [a, b])
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example (op : string) (a : term) : ¬ bin_only (term.app op [a]) :=
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begin
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intro h,
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cases h
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end
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example (op : string) (a b : term) (H : bin_only (term.app op [a, b])) : bin_only a :=
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begin
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cases H,
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assumption
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end
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example (op : string) (a b : term) (H : bin_only (term.app op [a, b])) : bin_only b :=
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begin
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cases H with _ _ _ _ H1 H2,
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exact H2
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end
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