I'm using the latest nXhtml checked out from the repo, and using GNU Emacs version 24.0.91.1. When I open a PHP file it shows as un-syntax-highlighted text, and I get a compile error:
Error: Wrong type argument: number-or-marker-p, nil
and a message in the log:
File mode specification error: (cl-assertion-failed (functionp byte-compiled-fun))
I'm avoiding my .emacs and .emacs.d by running emacs with this command:
emacs -Q --eval '(load "/path/to/nxhtml/autostart")' /path/to/nxhtml/tests/in/heredoc.php
Even if you don't have a fix, how can I go about debugging this issue?
There seem to be a fair amount of such wrong-type-argument errors lately with the development version of Emacs (24). This might represent an Emacs bug. Or it might represent an nXhtml bug.
I suggest starting by notifying Lennart, the nXhtml author, trying to give him a clear recipe, starting from emacs -Q.
If that doesn't help, consider filing an Emacs bug: M-x report-emacs-bug.
To try to debug it a bit yourself, be sure to load only source files (e.g. for nXhtml), i.e., *.el, not *.elc, starting preferably with emacs -Q (no init file). Do M-x set-variable debug-on-error t to see where the error is raised. Then perhaps use M-x debug-on-entry FUNCTION, where FUNCTION is the function where the error seems to have been raised. Then step through the Emacs debugger, hitting d to step and c to skip through a step.
But again, I suggest starting with Lennart.