[PATCH] Check 'x-resource is a specifier tag before passing it to map-specifier

[Stephen J. Turnbull]

Aidan Kehoe writes:

 > (I dislike the design of erroring when a specifier tag hasn't been
 > seen; this breaks run-time checks for, say, msprinter, for
 > example. But that's the way the design is right now.)

Ben?

Aidan, what do you think is sane behavior in that case?  It seems to
me that it's not obvious how matches with '(x not-yet-defined) should
be done.  In some cases you would want the match to succeed (because
the semantic requirement can't fail if the option is not there), in
others, to fail (because the semantic requirement can't succeed), no?