And if you don't trust the input, you can use the same technique more Safely like so: 

#!/usr/bin/perl
use warnings;
use strict;

use Safe;

my @ops = qw( padany leaveeval lineseq bit_or left_shift const
              left_shift right_shift bit_and bit_xor bit_or
              negate i_negate not complement);

my $safe = Safe->new();
$safe->permit_only(@ops);

my $result = $safe->reval( '(1 << 18) | (0x00 << 12) | (0x00 << 6) | 0
+x00' );
printf "0x%x\n", $result;

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-sauoq
"My two cents aren't worth a dime.";

In reply to Re: Convert bitwise value to its value by sauoq
in thread Convert bitwise value to its value by gibsonca

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