As http://www.jsoftware.com/help/primer/agreement.htm states in the last paragraph: "(...) one frame must be a prefix of the other (...)"
The frames of '',"0 [1 2 3 are 0 and 3, since 0=$'' and 3=$1 2 3 . Since 0 is not a prefix of 3 you get a length error. See also http://www.jsoftware.com/jwiki/Essays/A%20Fine%20Line Perhaps now you can work out the other examples yourself. Read also http://www.jsoftware.com/help/primer/result_shape.htm R.E. Boss > -----Oorspronkelijk bericht----- > Van: [email protected] [mailto:programming- > [email protected]] Namens Graham Parkhouse > Verzonden: zaterdag 28 augustus 2010 12:32 > Aan: [email protected] > Onderwerp: [Jprogramming] Rank zero append (,"0) > > > '',1 2 3 > 1 2 3 > NB. OK > '',"0 [1 2 3 > |length error > | '' ,"0[1 2 3 > NB. Is this because there are NO atoms in LH argument? > NB. I would have preferred to have seen 1 2 3 > 1 2 3,"0/ 4 5 6 > 1 4 > 1 5 > 1 6 > > 2 4 > 2 5 > 2 6 > > 3 4 > 3 5 > 3 6 > NB. OK > '',"0/ 4 5 6 > > NB. I would have preferred to have seen 4 5 6 > NB. Oddly: > '',"1 0/ 4 5 6 > 4 > 5 > 6 > NB. I'm struggling to understand the rules. > > Regards > > Graham > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
