#!/usr/bin/perl

use strict;
use warnings;

sub TIEHASH
{
	return bless {},$_[0];
}

sub FETCH
{
	return $_[1];
}

tie my %X,__PACKAGE__;

my $foo='look! no eval: 3735928559';
$foo=~s/(\d+)/$X{sprintf '0x%08X',$1}/;
print $foo;

##</code><code>##

>perl eval.pl
look! no eval: 0xDEADBEEF
>

##</code><code>##

#!/usr/bin/perl

use strict;
use warnings;

my $foo='look! no eval: 3735928559';
$foo=~s/(\d+)/${[sprintf '0x%08X',$1]}[0]/;
print $foo;

##</code><code>##

>perl eval2.pl
look! no eval: 0xDEADBEEF
>