         <%= text_input f, :for %>
         <%= submit "Search" %>
       <% end %>
+
+  `form_for/4` uses the `Plug.Conn` to set input values from the
+  request parameters. In this case, the input's value would be set
+  to `@conn.params["search"]["for"]`.
 
   ## Without form data
 

  Helpers related to producing HTML forms.

  The functions in this module can be used in three
  distinct scenario:

    * with model data - when information to populate
      the form comes from a model

      include an input tag with name `_csrf_token`. When set to false, this
      is disabled

    * `:enforce_utf8` - the form will have an `accept-charset` attribute set
      to "UTF-8" and a hidden input named `_utf8` containing a unicode
      character to force the browser to use UTF-8 as the charset. When set to
      false, this is disabled.


  See `Phoenix.HTML.Tag.form_tag/2` for more information on the
  options above.
