Records a theorem as a monotonicity theorem for inductive definitions.
DESCRIPTION
A call to export_mono "thm_name" causes the theorem of that name to
be stored as a monotonicity theorem, to be used when an inductive
definition is made. See the DESCRIPTION manual for more on the
required form of the theorem being exported in this way.
FAILURE
Fails if the string argument is not the name of a stored theorem. The
name can be qualified (preceded) with the name of an ancestral theory
segment and a full-stop, or can be “bare”, in which case it must be
the name of a theorem in the current segment.