> {-# LANGUAGE QuasiQuotes #-}
> {-# LANGUAGE TemplateHaskell #-}
> {-# LANGUAGE TypeFamilies #-}
> {-# LANGUAGE MultiParamTypeClasses #-}
> {-# LANGUAGE OverloadedStrings #-}
> {-# LANGUAGE CPP #-}
> import Yesod
> import Data.Text (Text)
> data I18N = I18N
> mkYesod "I18N" [parseRoutes|
> / HomepageR GET
> /set/#Text SetLangR GET
> |]
> instance Yesod I18N where
> approot _ = "http://localhost:3000"
> getHomepageR :: Handler RepHtml
> getHomepageR = do
> ls <- languages
> let hello = chooseHello ls
> let choices =
> [ ("en", "English") :: (Text, Text)
> , ("es", "Español")
> , ("he", "עִבְרִית")
> ]
> defaultLayout $ do
> setTitle "I18N Homepage"
> addHamlet [hamlet|
> <h1>#{hello}
> <p>In other languages:
> <ul>
> $forall choice <- choices
> <li>
> <a href="@{SetLangR (fst choice)}">#{snd choice}
> |]
> chooseHello :: [Text] -> Text
> chooseHello [] = "Hello"
> chooseHello ("he":_) = "שלום"
> chooseHello ("es":_) = "¡Hola!"
> chooseHello (_:rest) = chooseHello rest
> getSetLangR :: Text -> Handler ()
> getSetLangR lang = do
> setLanguage lang
> redirect RedirectTemporary HomepageR
> main :: IO ()
> main = warpDebug 3000 I18N
> _ignored :: Widget
> _ignored = undefined