> The interpreter knows what arrays it has;
> The interpreter can not do anything without
> allocating memory;
> The interpreter allocates memory in a single place;
> In the single place, apply the existing minus_zero
> eradicator to every array.

a. It doesn't just eradicate minus_zero in memory 
that it is allocating.  On every allocation of 
memory, it sweeps through every array that it has.

b. It can make a copy of any read-only arrays and
work only with that.

c. Since 15!:x is documented only for x e. i.5,
it is debatable whether you are using J at all
if you use stuff such as 15!:6 .



----- Original Message -----
From: Dan Bron <[EMAIL PROTECTED]>
Date: Monday, April 23, 2007 11:00 am
Subject: Re: [Jgeneral] zero

> Roger suggested:
> >In the single place, apply the existing minus_zero
> >eradicator to every array.
> 
> In the example I gave, the memory was already allocated.  I simply 
> modified it.  
> 
> Another exploit:  I could map a read-only file in one process, and 
> map that into J as a share.  Good luck applying your eradicator to 
> that.  
> 
> -Dan
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm

Reply via email to