the cookbook article http://symfony.com/doc/current/cookbook/cache/varnish.html currently provides vcl examples for varnish 2 with commented out varnish 3 options (with a bug: in varnish 3, purge should also be called in vcl_miss - its point is to remove all variants from the cache, even if its not all matching). also, the vcl example is first shown without acl (dangerous) and then just below duplicated with the vcl. and we completely miss varnish 4 docs.

i would like to do a PR to clean that up. ideally we could have config tabs for the vcl, like we have for xml / yaml / php config or twig / php templating. a while ago i opened fabpot/sphinx-php#16 (also talking about literalinclude which is not relevant here.) any chance we could do something like that? showing 3 versions of vcl mixed together, or one below the other, is not elegant.