Add from' for customization of labels and values.

src/Select.elm

@@ -1,16 +1,51 @@
-module Select exposing (from)
+module Select exposing (from, from')
+
+{-| This module provides the `Select.from` helper make working with `select`
+elements from Elm easier.
+
+# Helpers
+@docs from, from'
+
+-}
 
 import Html exposing (Html, option, select, text)
 import Html.Attributes exposing (value)
 import Html.Events exposing (onInput)
 
 
+{-| Convert a list of values and stringifying function for values of that type
+into a `select` element which contains as it's values the list of values.
+
+    from [North, South, East, West] Direction
+
+would produce a select element with box option values and labels being the
+string versions of four cardinal directions which would send messages
+like (Direction North) or (Direction East) when the user selects new directions
+from the drop down.
+
+-}
 from : List a -> (a -> msg) -> Html msg
 from xs msg =
+    from' xs msg toString toString
+
+
+{-| Convert a list of values and stringifying function for values of that type
+into a `select` element which contains as it's values the list of values.
+
+    from' [North, South, East, West] Direction toId toLabel
+
+would produce a select element with box option values and labels being decided
+by the `toId` and `toLabel` functions, which would send messages
+like (Direction North) or (Direction East) when the user selects new directions
+from the drop down.
+
+-}
+from' : List a -> (a -> msg) -> (a -> String) -> (a -> String) -> Html msg
+from' xs msg toId toLabel =
     let
         optionize x =
-            option [ (value << toString) x ]
-                [ (text << toString) x ]
+            option [ (value << toId) x ]
+                [ (text << toLabel) x ]
     in
         select [ onInput (msg << makeFromString' xs) ]
             (List.map optionize xs)