sub string_to_struct {
 my $string = shift;

 my ($var, $keys)  = split /-/, $string, 2;
 $keys = "-$keys"; # you could use a lookahead in the split, but in my experience they break on older Perl 5s.
 return 0 unless (
  $var eq "safe"
  or $var eq "alsosafe"
  ); 

 $change{$var}++; # global

 no strict refs;
 my $ref = $$var; # reference to the original. can alter the original
 use strict refs;
 return deref($ref, $keys);
}

sub deref {
 return \$_[0] unless $_[1] =~ s/^-([\w_]+)//; 
 deref ($_[0]->{$1}, $_[1]);
}

##</code><code>##

struct_to_string($safe,$safe->{foo},$safe->{foo}{bar});