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amalloy/freeVars.hs

Last active September 30, 2015 20:28
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freeVars.hs
freeVars :: Exp -> [Id]
freeVars (Var v) = [v]
freeVars (Nat _) = []
freeVars (Op _) = []
freeVars (Lam arg body) = delete arg $ freeVars body
-- freeVars (Lam arg body) = filter (/= arg) $ freeVars body
-- freeVars (Lam arg body) = delete arg . nub $ freeVars body
freeVars (App f x) = freeVars f ++ freeVars x
-- freeVars (App f x) = nub $ freeVars f ++ freeVars x
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