Re: certain strings both legal and illegal as associative array keys

[Greg Wooledge]

On Tue, Mar 03, 2015 at 01:55:55AM -0600, vampyrebat@gmail.com wrote:
> > imadev:~$ i="a'b"
> > imadev:~$ unset 'foo[$i]'
> 
> However, I did not try that way, because -- according to the bash
> documentation -- it shouldn't work.  Single quotes should prevent the
> expansion of $i.  Even knowing now that this does work, I can't find where
> this exception to single-quote behavior is documented.

Think of it as a two-step process.  The first step is ordinary expansion
and quote removal.  Since the $i is inside single quotes, it is not
expanded.  The quotes are removed, and we're left with foo[$i].

Then the array *itself* does a second expansion step, but it does so in a
context where the expanded contents cannot possibly be treated as syntax.
I don't think this is documented in the manual.