Re: [PATCH] add proper variable quoting to grub-mkconfig_lib (Debian bug #612417)

[Nicolas de Pesloüan]

Le 05/04/2011 21:32, Alexander Kurtz a écrit :
> Am Dienstag, den 05.04.2011, 21:16 +0200 schrieb Nicolas de Pesloüan:
> > Why do you use construct like "${x}" instead of "$x"?
>
> Because code isn't written once and then stays untouched forever. It
> changes over time and may be used in situations you did not anticipate.
> Writing solid code (and in shell scripts that definitely includes
> quoting your variables) avoids unnecessary bugs like this one.
>
> I've just seen too many poorly written shell scripts with hidden
> (sometimes even security-relevant) bugs to not do things properly.
>
> And it looks cleaner ;-)
>
> Best regards
>
> Alexander Kurtz

As Colin says, the {} construct is mostly useless and at least does not 
contribute to quoting.

On the same kind of things, the construct if test "x$foo" = "x" is pointless. It is a very strange 
heritage from DOS, where IF x%A = x was a common construct, because DOS (command.com) lack quoting. 
(Is wasn't possible to write IF "%a" = ""). In shell, "" is an empty string, but a real argument to 
commands. The following construct is the good one : if test "$foo" = "". The test command will 
receive three arguments: the value of $foo, the = sign and an empty argument and will return true if 
$foo happens to be empty.

Writing solid code imply - in particular - knowing the exact behaviors of the 
programming language :-)

I agree of course that this is definitely cosmetic, and this doesn't means that your work to remove 
unquoted variable is not good and necessary.

        Nicolas.