root@Captain:/home/pardus# perl
my $string = "print 'some string'; }";
my $sub = eval "sub { $string }";
print $@;

Unmatched right curly bracket at (eval 1) line 1, at end of line
syntax error at (eval 1) line 1, near "} }"
[download]

How about

my $string = '}{ print "Bwahaha!\n"; system("rm -rf /")';
[download]

Makeshifts last the longest.

Hmmm - I *really* should do development as a non-root user ...

But say I do pre-parse the string to check for unmatched curlies, I check for BEGIN and END blocks and I strip comments. Is eval "sub { $string }" usefull under these conditions ?

I don't care for security really -- I trust users to not intentionally fuck up the system.
--
Jaap Karssenberg || Pardus (Larus)? <pardus@cpan.org>
>>>> Zoidberg: So many memories, so many strange fluids gushing out of patients' bodies.... <<<<