Add HTMLDocument.currentScript and HTMLElement.getAttribute. (#4)

Add `HTMLDocument.currentScript`

Author: cprussin

src/Web/HTML/HTMLDocument.js

@@ -17,3 +17,9 @@ exports._activeElement = function (doc) {
     return doc.activeElement;
   };
 };
+
+exports._currentScript = function (doc) {
+  return function () {
+    return doc.currentScript;
+  };
+};

src/Web/HTML/HTMLDocument.purs

@@ -29,6 +29,7 @@ import Web.Event.EventTarget (EventTarget)
 import Web.HTML.HTMLDocument.ReadyState (ReadyState)
 import Web.HTML.HTMLDocument.ReadyState as ReadyState
 import Web.HTML.HTMLElement (HTMLElement)
+import Web.HTML.HTMLScriptElement (HTMLScriptElement)
 import Web.Internal.FFI (unsafeReadProtoTagged)
 
 foreign import data HTMLDocument :: Type
@@ -77,3 +78,8 @@ foreign import _activeElement :: HTMLDocument -> Effect (Nullable HTMLElement)
 
 activeElement :: HTMLDocument -> Effect (Maybe HTMLElement)
 activeElement = map toMaybe <<< _activeElement
+
+foreign import _currentScript :: HTMLDocument -> Effect (Nullable HTMLScriptElement)
+
+currentScript :: HTMLDocument -> Effect (Maybe HTMLScriptElement)
+currentScript = map toMaybe <<< _currentScript