22 lines
615 B
Elm
22 lines
615 B
Elm
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module Go.Util exposing (..)
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import Go.Types exposing (..)
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-- Search for a value in a list of key-value pairs.
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lookup : a -> List (a, b) -> Maybe b
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lookup val list = Maybe.map Tuple.second (List.head (List.filter (\(a, _) -> a == val) list))
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-- Computes all possible indices on a board of size n.
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allIndices : Int -> List Index
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allIndices n =
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let
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vals = List.range 0 (n - 1)
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pairs = \xs i -> List.map (\x -> (i, x)) xs
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in
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List.concatMap (pairs vals) vals
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zip : List a -> List b -> List (a, b)
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zip xs ys = case (xs, ys) of
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(x::xb, y::yb) -> (x, y) :: (zip xb yb)
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_ -> []
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