diff --git a/Language/Elm/Yesod.hs b/Language/Elm/Yesod.hs --- a/Language/Elm/Yesod.hs +++ b/Language/Elm/Yesod.hs @@ -1,4 +1,5 @@ {-# LANGUAGE QuasiQuotes, TypeSynonymInstances #-} +{-# LANGUAGE FlexibleInstances, MultiParamTypeClasses, TypeFamilies #-} {- | This module provides a function for compiling Elm source code into a Yesod widget. In order to use this with your Yesod app, you need to define a defaultLayout like function that embeds the elm-min.js file /in the tag/. @@ -7,16 +8,16 @@ > instance Yesod App where > jsLoader _ = BottomOfHeadBlocking -- moves JS to the tag - > defaultLayout widget = do - > pc <- widgetToPageContent $ do - > addScriptRemote $ "http://somecdn.org/link/to/elm-min.js" - > ... - > ... - A full example implementation is provided in the examples folder of the Elm github repository. + You also need to define an instance of 'YesodElm', which will specify + where to find the elm-min.js file. + + A full example implementation is provided in the examples folder of the Elm github repository + at . -} module Language.Elm.Yesod ( elmWidget + , YesodElm (..) , ElmUrl) where import Control.Monad (liftM) @@ -25,19 +26,32 @@ import Yesod.Core (Route (..)) import Yesod.Handler (getUrlRenderParams, GHandler (..)) import Yesod.Widget +import Yesod.Handler (lift, getYesod) import Language.Elm import Language.Elm.Quasi import qualified Data.Text as TS import qualified Data.Text.Lazy as TL +class YesodElm master where + -- | The location of the elm-min.js file. This can be either a type-safe + -- route (@Left@) or a raw string (@Right@). + urlElmJs :: a -> Either (Route master) TS.Text + +instance (YesodElm master, render ~ RenderFn (Route master)) + => ToWidget sub master (render -> Elm) where + toWidget = elmWidget + -- |elmWidget returns a Yesod widget from some Elm source code -- with URL interpolation. -elmWidget :: ElmUrl (Route master) -- ^ Elm source code - -> GHandler sub master (GWidget sub master()) +elmWidget :: YesodElm master + => ElmUrl (Route master) -- ^ Elm source code + -> GWidget sub master() elmWidget source = do - urlF <- getUrlRenderParams - return $ mkElmWidget source urlF + urlF <- lift getUrlRenderParams + mkElmWidget source urlF + master <- lift getYesod + addScriptEither $ urlElmJs master mkElmWidget :: ElmUrl (Route master) -- ^ Elm source code diff --git a/elm-yesod.cabal b/elm-yesod.cabal --- a/elm-yesod.cabal +++ b/elm-yesod.cabal @@ -1,5 +1,5 @@ Name: elm-yesod -Version: 0.1 +Version: 0.1.2 Synopsis: The Elm language Yesod compatibility module. Description: This module provides a simple function to embed Elm code as a Yesod widget.