lr =: 3 : '5!:5 <''y'''
lr is pretty cool:
lr 1 10 $ +: 5 * i:10
_100+10*i.1 10
with sparse arrays though, it does something weird and not obviously necessary:
lr $. 0 0 3 0 5
3 5 (2 4)}1$.(,5);(,0);0+-~2
lr 10 + $. 0 0 3 0 5 0
13 15 (2 4)}1$.(,6);(,0);10+-~2
The weird part is the little piece at the end. x+-~2 is x + 2 - 2 .... or x.
it also seems unnecessary for undoing?
$. inv ". '13 15 (2 4)}1$.(,6);(,0);10'
10 10 13 10 15 10
is this a bug in lr. For purposes of JON, i can add a check that allows
passive but rejects evoke, and it would only slow down parsing when ~ exists as
a standalone symbol, and I guess that seems necessary since this is not a bug,
but rather floating point adjustment:
lr 10.2 + $. 0 0 3 0 5 0
13.199999999999999 15.199999999999999 (2
4)}1$.(,6);(,0);10.199999999999999+-~2.1
----- Original Message -----
From: Pascal Jasmin <godspiral2...@yahoo.ca>
To: "programm...@jsoftware.com" <programm...@jsoftware.com>
Cc:
Sent: Wednesday, February 26, 2014 4:58:31 PM
Subject: Re: [Jprogramming] introducing JON alternative to JSON
Thank you Raul,
I've updated safe1 and safe2 to prevent arbitrary names that start with aLj...
apply was the problem rather than u: I hope.
safe1 =: '''_0123456789+*-<>|;,#{}()[]'
safe2 =: 'u:';'x:';'}.';'}:';'" ';'":';'! ';'$ ';'= ';'^
';'^.';'a.';'a:';'L.';'L:';'j.';'i.';'i:'
----- Original Message -----
From: Raul Miller <rauldmil...@gmail.com>
To: Programming forum <programm...@jsoftware.com>
Cc:
Sent: Wednesday, February 26, 2014 4:05:13 PM
Subject: Re: [Jprogramming] introducing JON alternative to JSON
On Wed, Feb 26, 2014 at 1:45 PM, Pascal Jasmin <godspiral2...@yahoo.ca> wrote:
> My big question though is have I overlooked any potential unsafe code that
> could be run with doSafe?
Yes.
Here's an example:
exploit=: smoutput@3:
doSafe '(u: ',(":u:inv 5!:5 <'exploit'),') apply 0'
3
Of course, there's not too much damage that a person could do with the
number 3, but hopefully the pattern is obvious.
Thanks,
--
Raul
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