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comparison demo/list.ur @ 397:4d519baf357c

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ListShop skeleton
author Adam Chlipala <adamc@hcoop.net>
date Tue, 21 Oct 2008 12:06:35 -0400
parents
children 7ef4b2911b09
comparison
equal deleted inserted replaced
396:040edfade639 397:4d519baf357c
1 datatype list t = Nil | Cons of t * list t
2
3 fun length' (t ::: Type) (ls : list t) (acc : int) =
4 case ls of
5 Nil => acc
6 | Cons (_, ls') => length' ls' (acc + 1)
7
8 fun length (t ::: Type) (ls : list t) = length' ls 0
9
10 fun rev' (t ::: Type) (ls : list t) (acc : list t) =
11 case ls of
12 Nil => acc
13 | Cons (x, ls') => rev' ls' (Cons (x, acc))
14
15 fun rev (t ::: Type) (ls : list t) = rev' ls Nil