Adding error feedbacks when adding a payment

3 files changed, 39 insertions, 0 deletions

diff --git a/src/client/Utils/Either.elm b/src/client/Utils/Either.elm
new file mode 100644
index 0000000..10c40e3
--- /dev/null
+++ b/src/client/Utils/Either.elm
@@ -0,0 +1,9 @@
+module Utils.Either
+  ( toMaybeError
+  ) where
+
+toMaybeError : Result a b -> Maybe a
+toMaybeError result =
+  case result of
+    Ok _ -> Nothing
+    Err x -> Just x
diff --git a/src/client/Utils/Maybe.elm b/src/client/Utils/Maybe.elm
new file mode 100644
index 0000000..507d9a4
--- /dev/null
+++ b/src/client/Utils/Maybe.elm
@@ -0,0 +1,9 @@
+module Utils.Maybe
+  ( isJust
+  ) where
+
+isJust : Maybe a -> Bool
+isJust maybe =
+  case maybe of
+    Just _ -> True
+    Nothing -> False
diff --git a/src/client/Utils/Validation.elm b/src/client/Utils/Validation.elm
new file mode 100644
index 0000000..0c1773e
--- /dev/null
+++ b/src/client/Utils/Validation.elm
@@ -0,0 +1,21 @@
+module Utils.Validation
+  ( validateNonEmpty
+  , validateNumber
+  ) where
+
+import String
+import Reads exposing (readInt)
+
+validateNonEmpty : String -> String -> Result String String
+validateNonEmpty message str =
+  if String.isEmpty str
+   then Err message
+   else Ok str
+
+validateNumber : String -> String -> Result String Int
+validateNumber message str =
+  case readInt str of
+    Just number ->
+      Ok number
+    Nothing ->
+      Err message