Ubuntu [Bug 791263] !$ works with `` but not $()

[Ralph Corderoy]

Hi,

I've just reported what I think to be a bug on Ubuntu but it's present
in pure bash 4.2 built from source too so I'm reporting it here.  I'm
not subscribed to the list so please CC me.  I take it there's no public
bug-tracker for bash and it's all done privately based on this list?

If any Ubuntu bashers have the odd spare minute then
https://bugs.launchpad.net/ubuntu/+source/bash/+bugs could do with a bit
of love and attention.  I've just marked invalid or fixed a few of the
bugs on there but there's plenty left.

Cheers, Ralph.

Report follows.

https://bugs.launchpad.net/ubuntu/+source/bash/+bug/791263

This is on 10.04 and also with upstream's pure bash 4.2 with no Debian
or Ubuntu patches.

    $ echo bar >foo
    $ >bar
    $ ls `cat foo`
    bar
    $ wc !$
    wc `cat foo`
    0 0 0 bar
    $ ls $(cat foo)
    bar
    $ wc !$
    wc )
    -bash: syntax error near unexpected token `)'
    $ ls $(<foo)
    bar
    $ wc !$
    wc )
    -bash: syntax error near unexpected token `)'
    $

I'd expect !$ to consider the last word to be $(...) just as it is happy
with `...`.  zsh does.