datatype 3 : 0 n=. 1 2 4 8 16 32 64 128 1024 2048 4096 8192 16384 32768 65536 131072 262144 t=. '/boolean/literal/integer/floating/complex/boxed/extended/rational' t=. t,'/sparse boolean/sparse literal/sparse integer/sparse floating' t=. t,'/sparse complex/sparse boxed/symbol/unicode/unicode4' (n i. 3!:0 y) pick <;._1 t )
None of t suggests a verb or function as a value. Conclusion: no such value type exists. If you're implementing a Scheme you'll probably want to tag all of your values. procedure? then would just be a check against the tag. On Thu, 2020-01-16 at 20:55 +0100, Raoul Schorer wrote: > Hi, > > I am translating scheme code that makes heavy use of delayed > evaluation > (thunks). In scheme, there is a predicate 'procedure?' that returns a > boolean. I translated that into a check for a boxed string, which is > the > representation I use for delayed procedures, which I then 'force' > using ".@> > > > 1. Is there a better way than building a program string to get > delayed > eval? I tried using (3: '(delayed_verb)"_'), but the interpreter > seems to > greedily eval the whole thing with that pattern. The only working > solution > I found was to convert everything to string. > 2. Is there a general test similar to 'procedure?' in J? > > > Thanks! > Raoul > ------------------------------------------------------------------- > --- > For information about J forums see > http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
