Richard Yao posted on Thu, 21 Jun 2012 20:38:17 -0400 as excerpted:

> Would you (or someone else) elaborate on the specific features of bash
> that people find attractive?

For me (not a gentoo dev), in simplest terms it's just that I don't like 
having to keep track of what's a bashism and what's POSIX.  If individual 
devs prefer POSIX code, they can certainly write ebuilds (or a 4th gentoo 
package manager for that matter) in all POSIX, but there's enough devs 
that for /whatever/ reason strongly prefer bash, where "strongly" is 
ultimately defined as "if it's redefined to POSIX, there's a lot of other 
projects I can spend my time on instead, that won't force me into jumping 
thru those hoops", and that fact is widely enough known, that it's 
unlikely in the extreme.

But to give you a example I've seen on this list (one of the few bits I 
know isn't POSIX)...  Many people appreciate the advantages of [[ tests, 
looser quoting, ==/=~ pattern matching tests, etc.

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman