The explicit definition documentation (http://www.jsoftware.com/help/dictionary/d310n.htm and/or http://www.jsoftware.com/docs/help701/dictionary/d310n.htm) explains the "13 : n" case as "tacit verb if possible, otherwise equivalent to 3 : n".
Should this not include mention of "4 : n" where 'x' is present in the verb body? Best, Marc ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
