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Fix a variable capture bug in nested JavaScript; some more list stuff
author Adam Chlipala <adamc@hcoop.net>
date Tue, 16 Jun 2009 17:52:44 -0400
parents 0d30e6338c65
children ed06e25c70ef
comparison
equal deleted inserted replaced
849:e571fb150a9f 850:1c2f335297b7
29 | x :: ls => foldl' (f x acc) ls 29 | x :: ls => foldl' (f x acc) ls
30 in 30 in
31 foldl' 31 foldl'
32 end 32 end
33 33
34 fun foldlPartial [a] [b] f = 34 fun foldlAbort [a] [b] f =
35 let 35 let
36 fun foldlPartial' acc ls = 36 fun foldlAbort' acc ls =
37 case ls of 37 case ls of
38 [] => Some acc 38 [] => Some acc
39 | x :: ls => 39 | x :: ls =>
40 case f x acc of 40 case f x acc of
41 None => None 41 None => None
42 | Some acc' => foldlPartial' acc' ls 42 | Some acc' => foldlAbort' acc' ls
43 in 43 in
44 foldlPartial' 44 foldlAbort'
45 end 45 end
46 46
47 val rev = fn [a] => 47 val rev = fn [a] =>
48 let 48 let
49 fun rev' acc (ls : list a) = 49 fun rev' acc (ls : list a) =
52 | x :: ls => rev' (x :: acc) ls 52 | x :: ls => rev' (x :: acc) ls
53 in 53 in
54 rev' [] 54 rev' []
55 end 55 end
56 56
57 fun foldlMapAbort [a] [b] [c] f =
58 let
59 fun foldlMapAbort' ls' acc ls =
60 case ls of
61 [] => Some (rev ls', acc)
62 | x :: ls =>
63 case f x acc of
64 None => None
65 | Some (x', acc') => foldlMapAbort' (x' :: ls') acc' ls
66 in
67 foldlMapAbort' []
68 end
69
57 val revAppend = fn [a] => 70 val revAppend = fn [a] =>
58 let 71 let
59 fun ra (ls : list a) acc = 72 fun ra (ls : list a) acc =
60 case ls of 73 case ls of
61 [] => acc 74 [] => acc