PRFW-^PN : INFOPRFW-^PN is a flag setting or other piece of information.
An option for ETREE-NAT-VERBOSE.
After each tactic during ETREE-NAT, in the proofwindow "Current Subproof
and Line Numbers", print the current plan-support pair in the proof, and
also print just the line numbers of the other lines in the proof.
ETPS documentation homepage