De Bruijn indices
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module Main
import Data.Fin
data Term : Nat -> Type where
BVar : Fin n -> Term n
FVar : String -> Term n
Abs : Term (n + 1) -> Term n
App : Term n -> Term n -> Term n
exampleId : Term 0
exampleId = Abs (BVar 0)
exampleConst : Term 0
exampleConst = Abs (Abs (BVar 1))
-- exampleIll : Term 0
-- exampleIll = BVar 0
main : IO ()
main = putStrLn "Hello World!"
Idris
INFO