From: KOSAKI Motohiro <kosaki.motohiro@...>
Date: 2013-03-24T04:30:25+09:00
Subject: [ruby-core:53680] Re: [ruby-core:53679] Why doesn’t String#+ return an untrusted result if self or other is untrusted?

On Sat, Mar 23, 2013 at 2:45 PM, Nikolai Weibull <now@bitwi.se> wrote:
> Hi!
>
> Why doesn�t String#+ return an untrusted result if self or other is untrusted?
>
> Only taint is inherited.
>
> Also, I can�t really find any documentation on the difference between
> taint and untrust.

IIUC, untrusted mean an object was created from untrusted code (i.e. $SAFE >=3).
taint mean the data is derived from other tainted data or IO source.

That said, when trusted code (i.e. $SAFE=0) call String#+, ruby assume caller
understand what String#+ does.