I'm running WordPress on HHVM and I'd like to develop themes, plugins and templates with Hack and XHP, rather than PHP. I have noted, that while <?php /* Template Name: Hack/HHVM test */ ?> (in a file with a .php extension) can be used to create a new page-template, <?hh /* Template Name: Hack/HHVM test */ ?> (in a file with a .hack) isn't even recognized. Is WordPress development currently lacking support for Hack? What information can be provided on this topic?
The .hhconfig file wasn't present, and that's what was blocking me. Otherwise WordPress has support for developing with Hack. I have a plugin implementation running now.
Note: The file extension can be either .php or .hh but not .hack (documentation), and the file opens with <?hh.