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module Misc exposing (..)
import Array exposing (Array)
comesAfter : a -> List a -> Maybe a
comesAfter x xs =
case xs of
[] ->
Nothing
_ :: [] ->
Nothing
y :: z :: rest ->
if y == x then
Just z
else
comesAfter x (z :: rest)
comesBefore : a -> List a -> Maybe a
comesBefore x xs =
case xs of
[] ->
Nothing
_ :: [] ->
Nothing
y :: z :: rest ->
if z == x then
Just y
else
comesBefore x (z :: rest)
find : (a -> Bool) -> List a -> Maybe a
find pred xs =
case xs |> List.filter pred of
[] ->
Nothing
x :: _ ->
Just x
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