17 lines
303 B
Text
17 lines
303 B
Text
inductive S where
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| P
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| I
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open S
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inductive Expr : S → Type where
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| lit : Int → Expr I
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| eq : Expr I → Expr I → Expr P
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def Val : S → Type
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| P => Prop
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| I => Int
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def eval : {s : S} → Expr s → Val s
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| _, (Expr.lit n) => n
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| _, (Expr.eq e₁ e₂) => eval e₁ = eval e₂
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