Re: User-reserved element in byte code vectors

[Richard Stallman]

I recommend leaving the first slot after `curry' unused.  That way it
could be used later to control extensions, such as a feature to
specify the order of curried and noncurried arguments.

Meanwhile, the biggest part of this job remains to be done.  That is
to update etc/NEWS and the Lisp manual.  I think that we should not
install this feature unless those changes are written first.