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Handle nullary transaction pages; avoid marking up headers array when reading cookies
author Adam Chlipala <adamc@hcoop.net>
date Tue, 11 Nov 2008 18:39:38 -0500
parents 4d519baf357c
children 7ef4b2911b09
line wrap: on
line source
datatype list t = Nil | Cons of t * list t

fun length' (t ::: Type) (ls : list t) (acc : int) =
    case ls of
        Nil => acc
      | Cons (_, ls') => length' ls' (acc + 1)

fun length (t ::: Type) (ls : list t) = length' ls 0

fun rev' (t ::: Type) (ls : list t) (acc : list t) =
    case ls of
        Nil => acc
      | Cons (x, ls') => rev' ls' (Cons (x, acc))

fun rev (t ::: Type) (ls : list t) = rev' ls Nil