ruby on rails - How to stop outputing my own html source? -

this may werdeist bug i've ever met.

i'm building app personal use on ruby on rails, , it's still long way done. main layout follows:

!!! %html.uk-height-1-1 %head     = render 'layouts/head' %body.uk-height-1-1.uk-width-1-1     = if user_signed_in?         .alerts             = render 'layouts/alerts'         .navbar             = render 'layouts/navbar'     .uk-container.uk-height-1-1         = yield     = if user_signed_in?         .footer             = render 'layouts/footer' 

the alerts , footer partials still empty, head partial default code rails generates (minus turbolinks) , navbar partial is, well, navbar. change made on application controller adding before_action :authenticate_user!, users logged in can see main site.

but run server, following showed up:

it outputs it's own html source code plain text!
, twice: first, right after navbar partial, , last after footer partial.
i've never met close this, , attempt find source of error useless.
how can stop this, or @ least find reason of madness?

replace both of = if - if.

lines starting = append return value of if statement view, non-html safe string.

lines starting - evaluated ruby code without appending view.