Note also that ‘’ {:: 0 works, and also the typical case left argument for
{:: might be a boxed list.— Raul On Tuesday, September 18, 2018, Henry Rich <[email protected]> wrote: > By all means put it on the list. > > You are selecting along 1 axis from an argument that has 0 axes, which > makes the length error reasonable. > > The question is, why does 0 { 0 not fail? Answer: because of the fine > print in the definition. (0 { y) selects item number 0, and an atom has a > single item, itself. > > (<0) { 5 fails, rightly, for the same reason 0 {:: 5 fails. > > It is important to get these edge cases right, and there's most often only > one right way, so my assumption is that Roger did it the right way. I'll > have to think it over. > > Henry Rich > > > > On 9/18/2018 8:05 PM, 'Pascal Jasmin' via Programming wrote: > >> I can add to request list. >> >> The argument for is that it is a source of "needless" errors. The error >> applies also if there is a nested box structure, but the top level is an >> atom. >> >> Perhaps there is a performance reason against it. >> >> I would doubt that existing code in the wild relies on the error for any >> other purpose than to convert the scalar into a list of 1 item. >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm >> > > > --- > This email has been checked for viruses by AVG. > https://www.avg.com > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
