What you are arguing for is that $ 5 +"1 (0 1$' ') should be 0 but that $ 5 +"1 (0 1$0 ) should be 0 1 . Is that really what you want your stock trading program to depend on?
----- Original Message ----- From: Henry Rich <[EMAIL PROTECTED]> Date: Wednesday, July 5, 2006 7:55 pm Subject: RE: [Jbeta] Incorrect result shape from 5 +"1 (0 1 $' ') > What I meant was, if I have defined > > plus =: + > > then +"1 and plus"1 should always get the same result. > (That's why I wrote 'plus' rather than 'f'). > > The interpreter doesn't need to know that + and plus are > the same. All it needs to do is follow the rule for > empties, which requires checking the type, because the > cell of fills is typed. > > I don't remember how I got into looking at 5+"1 (0 1$' ') > but that isn't important. The practical difference to > me between 0 1$0 and 0$0 is that > (0 1$0) , 0$0 > 0 > (0 1$0) , 0 1$0 > > in other words, the wrong shape produces a list with > one item when it should have 0 items. > > Maybe that won't matter - it might just be something > on the screen a few seconds. Or, it might be a list > of stock transactions to perform, in which case I will > incorrectly commit 25% of my net worth to a bad stock. > (This has actually happened. Last time the stock went > up). > > So I really want rules to go by. Learning by experiment > can be awfully expensive. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
