` should display the content of the article. We should also declare some another model object. Add this in the `config/models` file:

Article
    title   Text
    content Html 
    deriving

Why add the `deriving` is not obvious. There is a technical reason behind it. You have to remember to add it if you use a type which is not an instances of `Read`, `Show` and `Eq` like `Html` in this case. If you forget it, there will be an error. Now we have prepared the route and the model, we should write the actual code. pre Let's declare a new Handler module. Add `import Handler.Blog` inside `Application.hs` and add it into `yosog.cabal`. Now let's write the content of `Handler/Blog.hs`. We start by declaring the module and by importing some block necessary to handle Html in forms.


module Handler.Blog
    ( getBlogR
    , postBlogR
    , getArticleR
    )
where

import Import

To use Html in forms


import Yesod.Form.Nic (YesodNic, nicHtmlField)
instance YesodNic Yosog

Define a form for adding a new article. Don't pay attention to all the syntax. If you are curious you can take a look at Applicative Functor. You just have to remember `areq` is for required form input. Its arguments being: `areq type label default_value`.


entryForm :: Form Article
entryForm = renderDivs $ Article
    <$> areq   textField "Title" Nothing
    <*> areq   nicHtmlField "Content" Nothing


-- The view showing the list of articles
getBlogR :: Handler RepHtml
getBlogR = do
    -- Get the user. Yes, it's that simple.
    muser <- maybeAuth
    -- Get the list of articles inside the database.
    articles <- runDB $ selectList [] [Desc ArticleTitle]
    -- We'll need the two "objects": entryWidget and enctype
    -- to construct the form (see template/articles.hamlet).
    ((_,entryWidget), enctype) <- generateFormPost entryForm
    defaultLayout $ do
        $(widgetFile "articles")

Just take a look at the content of `template/articles.hamlet`.

`Articles $if null articles -- There are no article. $else --`
`$forall article <- articles`
`#{articleTitle (snd article)} -- $maybe (_, user) <- muser --`
`Write a new one ^{entryWidget}`
`-- $nothing --`
`Login to Post` The syntax is a bit strange, but you get the idea easily. postBlogR :: Handler RepHtml postBlogR = do ((res,entryWidget),enctype) <- runFormPost entryForm case res of FormSuccess article -> do articleId <- runDB $ insert article setMessageI $ MsgEntryCreated $ articleTitle article redirect RedirectPermanent $ ArticleR articleId _ -> defaultLayout $ do setTitleI MsgPleaseCorrectEntry $(widgetFile "articleAddError") getArticleR :: ArticleId -> Handler RepHtml getArticleR articleId = do article <- runDB $ get404 articleId muser <- maybeAuth defaultLayout $ do $(widgetFile "article")
--- <%= startTodo %>

Create a minimal blog system.
Change template to %html5 boilerplate.
Use Authentification.

<%= endTodo %>

#{theText}|] ### Use a new template file The last thing to change in order to do things like in a real project is to use another template file. Just create a new file `template/echo.hamlet` containing:

Enter your text You've just posted #{postedText}

You've just posted #{postedText}

Articles $if null articles -- There are no article. $else --

Write a new one ^{entryWidget} -- $nothing --