DB<105> sub delchar { my $m; $m = $1 if $x =~ s/(\w)//;  $m ?  $m . delchar() . $m : "-"  }
 => 0
 
  DB<106> $x='abc'; delchar()
 => "abc-cba"
 
  DB<107> sub delchar { local $m; $m = $1 if $x =~ s/(\w)//;  $m ?  $m . delchar() . $m : "-"  }
 => 0
 
  DB<108> $x='abc'; delchar()
 => "abc-cba"