$ perl -l -
print for $$,  ${ '::$' },  ${  $main::{ '$' }  };
&{  $main::{ '$'  }  };
__END__
2840
2840
2840
Undefined subroutine &main::$ called at - line 2.

##</code><code>##

 $ perl -e " use Data::Dump::Streamer; Dump $main::{ q{$} }; "
$VAR1 = *{'::$'};
*{'::$'} = \4032;

$ perl -e " use Data::Dump; dd $main::{ q{$} }; "
do {
  my $a = *main::$;
  $a = \2104;
  $a;
}