Merge pull request #1042 from yesodweb/add_getsYesod_function

Added getsYesod
yesodweb · Jul 23, 2015 · 4865702 · 4865702
2 parents 81c996f + c4d154b
commit 4865702
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/yesod-core/Yesod/Core/Handler.hs b/yesod-core/Yesod/Core/Handler.hs
@@ -28,6 +28,7 @@ module Yesod.Core.Handler
       HandlerT
       -- ** Read information from handler
     , getYesod
+    , getsYesod
     , getUrlRender
     , getUrlRenderParams
     , getCurrentRoute
@@ -291,6 +292,11 @@ askHandlerEnv = liftHandlerT $ HandlerT $ return . handlerEnv
 getYesod :: MonadHandler m => m (HandlerSite m)
 getYesod = rheSite `liftM` askHandlerEnv
 
+-- | Get a specific component of the master site application argument. 
+--   Analogous to the 'gets' function for operating on 'StateT'.
+getsYesod :: MonadHandler m => (HandlerSite m -> a) -> m a
+getsYesod f = (f . rheSite) `liftM` askHandlerEnv
+
 -- | Get the URL rendering function.
 getUrlRender :: MonadHandler m => m (Route (HandlerSite m) -> Text)
 getUrlRender = do