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|
fun foldlAbort [a] [b] [c] f =
let
fun foldlAbort' acc ls1 ls2 =
case (ls1, ls2) of
([], []) => Some acc
| (x1 :: ls1, x2 :: ls2) =>
(case f x1 x2 acc of
None => None
| Some acc' => foldlAbort' acc' ls1 ls2)
| _ => None
in
foldlAbort'
end
fun mapX [a] [b] [ctx ::: {Unit}] f =
let
fun mapX' ls1 ls2 =
case (ls1, ls2) of
([], []) => <xml/>
| (x1 :: ls1, x2 :: ls2) => <xml>{f x1 x2}{mapX' ls1 ls2}</xml>
| _ => error <xml>ListPair.mapX: Unequal list lengths</xml>
in
mapX'
end
fun all [a] [b] f =
let
fun all' ls1 ls2 =
case (ls1, ls2) of
([], []) => True
| (x1 :: ls1, x2 :: ls2) => f x1 x2 && all' ls1 ls2
| _ => False
in
all'
end
fun mp [a] [b] [c] (f : a -> b -> c) =
let
fun map' ls1 ls2 =
case (ls1, ls2) of
([], []) => []
| (x1 :: ls1, x2 :: ls2) => f x1 x2 :: map' ls1 ls2
| _ => error <xml>ListPair.mp: Unequal list lengths</xml>
in
map'
end
fun mapM [m] (_ : monad m) [a] [b] [c] (f : a -> b -> m c) =
let
fun mapM' ls1 ls2 =
case (ls1, ls2) of
([], []) => return []
| (x1 :: ls1, x2 :: ls2) =>
y <- f x1 x2;
ls <- mapM' ls1 ls2;
return (y :: ls)
| _ => error <xml>ListPair.mapM: Unequal list lengths</xml>
in
mapM'
end
fun unzip [a] [b] (ls : list (a * b)) : list a * list b =
let
fun unzip' ls ls1 ls2 =
case ls of
[] => (List.rev ls1, List.rev ls2)
| (x1, x2) :: ls => unzip' ls (x1 :: ls1) (x2 :: ls2)
in
unzip' ls [] []
end
|
