Here is a buggy first draft attempt implementation for http://rosettacode.org/wiki/Man_or_boy_test
(where the big problem is figuring out what the specification is saying.) A=:1 :0 '`x1 x2 x3 x4 x4'=.m k=.y B=. ". bind 'B`x1`x2`x3`x4 A k'@(".bind 'k=.k-1') if.k<:0 do.(x4+x5)'' else. B''end. ) smoutput 1:`_1:`_1:`1:`0: A 10 When run, J spins and ignores jbreak. (If x4 x4 is replaced with x4 x5 we instead get a stack error.) FYI, -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm