Don Guinn <[EMAIL PROTECTED]> wrote: > Why do you say adding support for undotted parameters would break > existing code? As it stands now when 1=9!:48'' J6 works like J5 as far > as parameter names are concerned.
Not totally. The default assigns values to BOTH y and y. This means that now, explicit definitions that could see globals like y will now see locals with the same name. y =: 5 jVersion =: 3 : 'y' @ 6: jVersion'' 5 If you run this on J 6, the result will be 6 instead of 5 y =: 0 IncY =: 3 : 'y=:>:y' IncY 7 1 y 1 This produces a domain error in J 6 when trying to assign to global y Even if the J 6 safety that forbids such assignments were not back-ported to J 5, this function would return 8 instead of 1 (and change the global accordingly). x =: +/ .* MatAtimesBtimesA =: 4 : 'x. x y. x x.' This was fine in J 5, but under J 6, it is now a disaster waiting to happen. -- Mark D. Niemiec <[EMAIL PROTECTED]> ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
