31 lines
781 B
Lean4
31 lines
781 B
Lean4
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import BidirTT.Value
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namespace BidirTT
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structure Cxt where
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env : Env
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types : List (Name × Val)
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lvl : Lvl
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deriving Inhabited
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def Cxt.empty : Cxt := ⟨[], [], 0⟩
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def Cxt.bind (cxt : Cxt) (x : Name) (a : Val) : Cxt :=
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{ env := .var cxt.lvl :: cxt.env
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, types := (x, a) :: cxt.types
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, lvl := cxt.lvl + 1 }
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def Cxt.define (cxt : Cxt) (x : Name) (v a : Val) : Cxt :=
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{ env := v :: cxt.env
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, types := (x, a) :: cxt.types
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, lvl := cxt.lvl + 1 }
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private def lookupGo : Name → List (Name × Val) → Nat → Option (Nat × Val)
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| _, [], _ => none
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| x, (y, a) :: rest, i => if x == y then some (i, a) else lookupGo x rest (i+1)
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def Cxt.lookup (cxt : Cxt) (x : Name) : Option (Nat × Val) :=
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lookupGo x cxt.types 0
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end BidirTT
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