sub foo;
print ref \$::{foo}; # "SCALAR"

sub bar { 1 };
print ref \$::{bar}; # "GLOB"

sub baz;
print ref \$::{baz}; # "GLOB"
$baz = $baz;         # Just to mention the symbol "baz".

##</code><code>##

sub foo;
*{-1} = sub { 'oh' };     # Create a sub called "-1".
print &{-1}();            # "oh"
*bar = $::{foo};          # Really?
print defined &bar;       # "1" Huh? So now &bar is defined
                          # even though &foo isn't?
print bar();              # "oh"

#$foo;                    # But all this would change if you
                          # uncommented "$foo;".