Merge pull request #10 from bbarker/nodeValue_maybe

fixes #9 : nodeValue should return Effect (Maybe String)

Author: garyb

src/Web/DOM/Node.js

@@ -40,7 +40,7 @@ exports._previousSibling = getEffProp("previousSibling");
 
 exports._nextSibling = getEffProp("nextSibling");
 
-exports.nodeValue = getEffProp("nodeValue");
+exports._nodeValue = getEffProp("nodeValue");
 
 exports.setNodeValue = function (value) {
   return function (node) {

src/Web/DOM/Node.purs

@@ -121,9 +121,12 @@ nextSibling = map toMaybe <<< _nextSibling
 
 foreign import _nextSibling :: Node -> Effect (Nullable Node)
 
--- | If the node type is text, comment, or processing instruction this is the
--- | node's data, or null in all other cases.
-foreign import nodeValue :: Node -> Effect String
+-- | If the node type is text, comment, or processing instruction this is
+-- | `Just` the node's data, or `Nothing` in all other cases.
+nodeValue :: Node -> Effect (Maybe String)
+nodeValue = map toMaybe <<< _nodeValue
+
+foreign import _nodeValue :: Node -> Effect (Nullable String)
 
 -- | If the node type is text, comment, or processing instruction this allows
 -- | the node's data to be changed, or has no effect in all other cases.