Is there some reliable way that a subroutine can gain access to itself as a code reference? I can do this as a closure but I wondered if there was something generalizable so any subroutine, closure or not, could alter itself.

I'm specifically thinking of subroutines that can terminate themselves and prevent further access. Here's a code snippet where I'm hoping for something more general.

sub purse
  {
    my $balance = shift;
    my $sub;
    $sub = sub { my ($who, $qty) = @_;
                 print "Paying $who $qty\n"
                   if ($balance - $qty) >= 0;
                 undef $sub
                   if $balance <= 0 };
  }

{
  my $payment = purse(10);
  for ([qw/mom 7/],
       [qw/dad 3/],
       [qw/myself 1/])
    {
      $payment->(@$_) if $payment;
    }
}

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In reply to Giving subroutines access to themselves by diotalevi

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