Playing around with Safe.pm to write a prog that would safely allow users to enter test strings and regexes and test matching. Found the following:

#!/usr/bin/perl -w

use Safe;
$c = new Safe;

$c->permit_only( 
    qw(
        leaveeval
        const
    ));

$result = $c->reval('"A" =~ m/a/i') ? 'YES' : 'NO';

die "$@\n" if $@;

print "\$result = $result\n";

__END__
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This works, even though I didn't permit 'match'.

Current output is "$result = YES".

Changing regex to delete the i causes "$result = NO"

eliminating either OP in the permit_only() cause the $c->reval to fail compilation with "<OP> item trapped by operation mask at (eval 2) line 1", as expected.

Shouldn't I need to permit 'match' for this to pass reval()?

This happens on perl 5.005_03, 5.6.0 and 5.8.0 on Linux, and , perl 5.6.1 form Activestate on WinNT. (The code on 5.8.0 permitted a few more OPs but still worked without 'match'). Since it happens on so many systems, I'm thinking I'm just missing something obvious.

--Bob Niederman, http://bob-n.com