Yes, Hamlet does context specific escaping. It will handle all the examples given, except you can't mix your javascript in with your html (which is generally good advice anyways).

I disagree with the articles premise that injection is always a display issue. In the [Yesod web framework](http://www.yesodweb.com) which uses Hamlet, we sanitize, not strip html by default before it is ever put in the database. The more you can make injection not a display issue, the better- you just have to know your options.