Re: bash: History substitution doesn't happen after ^V^J.

[Ralph Corderoy]

Hi Chet,

> >     $ echo !$<Return>
> >     foo
> >     $ echo 'a^V^J
> >     b' !$<Return>
> >     a
> >     b !$
> >     $
> 
> History expansion is done on a per-line basis, not per-token.  It is
> performed before the shell parser sees the line.

OK.

> At the point the second line is read and history expanded, the
> parser's state is still `open single quote', so expansion is
> inhibited.

I understand.

> I'd rather err on the side of not performing history expansion where
> it could possibly be done instead of performing it when it should not.

Couldn't we pick the middle ground and do it when it's right and not
when it's not?  :-)  That

    $ echo 'a b' !$
    $ echo 'a
    b' !$

produce different results seems to be a bug, even if it the behaviour is
understandable.

There's already quoted-histchar-checking present that stops expansion:

    $ echo foo
    foo
    $ echo !$ \!$ 'a !$ b' \
    > !$ z
    foo !$ a !$ b  z
    $ 

Wouldn't it just be in the in-quoted-string state at the beginning of
line two but leave that on encountering the close quote?

I've no patch to provide, but I'd rather see this left open as a bug to
be fixed one day rather than closed under `as designed'.

Cheers,


Ralph.