Initial version.

Features:

- Upload PDF files let them analyze

- Manage meta data and items

- See processing in webapp

modules/webapp/src/main/elm/Util/List.elm

@@ -0,0 +1,53 @@
+module Util.List exposing ( find
+                          , findIndexed
+                          , get
+                          , distinct
+                          , findNext
+                          , findPrev
+                          )
+
+get: List a -> Int -> Maybe a
+get list index =
+    if index < 0 then Nothing
+    else case list of
+        [] ->
+            Nothing
+        x :: xs ->
+            if index == 0
+            then Just x
+            else get xs (index - 1)
+
+find: (a -> Bool) -> List a -> Maybe a
+find pred list =
+    findIndexed pred list |> Maybe.map Tuple.first
+
+findIndexed: (a -> Bool) -> List a -> Maybe (a, Int)
+findIndexed pred list =
+    findIndexed1 pred list 0
+
+findIndexed1: (a -> Bool) -> List a -> Int -> Maybe (a, Int)
+findIndexed1 pred list index =
+    case list of
+        [] -> Nothing
+        x :: xs ->
+            if pred x then Just (x, index)
+            else findIndexed1 pred xs (index + 1)
+
+distinct: List a -> List a
+distinct list =
+    List.reverse <|
+        List.foldl (\a -> \r -> if (List.member a r) then r else a :: r) [] list
+
+findPrev: (a -> Bool) -> List a -> Maybe a
+findPrev pred list =
+    findIndexed pred list
+        |> Maybe.map Tuple.second
+        |> Maybe.map (\i -> i - 1)
+        |> Maybe.andThen (get list)
+
+findNext: (a -> Bool) -> List a -> Maybe a
+findNext pred list =
+    findIndexed pred list
+        |> Maybe.map Tuple.second
+        |> Maybe.map (\i -> i + 1)
+        |> Maybe.andThen (get list)