Tricky... I hate to risk crying wolf, but there may be a Perl bug going on here.

I'm assuming that this is the beginning stage of a japh?

Although I haven't solved the problem, I'm posting a slightly more untangled version of the code (think of it as a preemptive deobfuscation) in order to make the problem a bit clearer.

On perl 5.6.1 on Linux, this code returns "func MAIN returns func B returns 1+C(2)", when by intuition it should return "func MAIN returns func B returns 1+2". On perl 5.6.1 on Windows, the program coredumps.

use strict;

print doFunc( "MAIN", "B(1)+C(2)" );

sub doFunc{
  my ($theFunc, $rem) = @_;

  my $re = &get_re($rem);

  $rem =~ s/(\w+)\(($re)\)/&doFunc($1,$2)/eg;
  return "func $theFunc returns $rem";
}

##
## When we're called with the initial
## state, return "1|2". Otherwise, return
## our input, quotemeta'd.
##
sub get_re {
  my ($in) = @_;

  if ($in eq "B(1)+C(2)") {
    return '1|2';
  }
  else {
    return quotemeta($in);
  }
}
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stephen