Why this doesn't work in zsh?

Why this doesn't work in zsh?

[DervishD]

    Hi all :))

    I have part of a script that says something like:

    for parameter
    do
    ...
        option=${parameter%=*}
    ...
    done

    This assign the part before '=' to variable 'option', no more, no
less, and uses parameter expansion.

    It has to work with both bash and zsh, but zsh says, when the
assignment is done, '* not found'.

    The problem is the equalsign on the parameter expansion, now I
know, but, why? How can I fix this without making the script
incompatible with bash? What am I doing wrong?

    Thanks a lot :)
    Raúl

Re: Why this doesn't work in zsh?

[Peter Stephenson]

DervishD wrote:
>     for parameter
>     do
>     ...
>         option=${parameter%=*}
>     ...
>     done
> 
>     It has to work with both bash and zsh, but zsh says, when the
> assignment is done, '* not found'.

You can stick a backslash before the =; that works in bash, too, since
you can quote any character, even if it's not special.

The problem is that it's using path expansion `=prog', but I couldn't
tell you why it should at that point; in fact, I suspect it shouldn't.
Hence `setopt noequals' or `setopt nonomatch' would remove the problem,
if you can live with the side effects.

-- 
Peter Stephenson <pws@csr.com>                  Software Engineer
CSR Ltd., Science Park, Milton Road,
Cambridge, CB4 0WH, UK                          Tel: +44 (0)1223 692070


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Re: Why this doesn't work in zsh?

[DervishD]

    Hi Peter :)

> >     It has to work with both bash and zsh, but zsh says, when the
> > assignment is done, '* not found'.
> You can stick a backslash before the =; that works in bash, too, since
> you can quote any character, even if it's not special.

    OK, then, that's the solution :)) Thanks a lot :)

> The problem is that it's using path expansion `=prog', but I couldn't
> tell you why it should at that point; in fact, I suspect it shouldn't.
> Hence `setopt noequals' or `setopt nonomatch' would remove the problem,
> if you can live with the side effects.

    Yes, the problem is noequals, I discovered after sending the
message. I can live with side effects, of course, but the problem is
that I cannot tell the script users to set appropriate options when
running this on their systems. The better solution is to quote the
character. Thanks a lot :)))

    Raúl