import "Prelude"

inc :: Ref Integer -> <Proc> Integer
inc r = do 
    v = getRef r
    newV = v+1
    r := newV
    newV

main = do
    r = ref 0
    l = map (\_ -> inc r) [1..4]
    r := 4 // Map must be executed before this statement
    foldl (+) 0 l
--
10