print OUT;

##</code><code>##

$ perl -wle 'print OUT'
Name "main::OUT" used only once: possible typo at -e line 1.
print() on unopened filehandle OUT at -e line 1.

##</code><code>##

$ perl -wle 'print $fh'
Name "main::fh" used only once: possible typo at -e line 1.
Use of uninitialized value in print at -e line 1.

$ perl -wle 'print $fh $bar'
Name "main::bar" used only once: possible typo at -e line 1.
Name "main::fh" used only once: possible typo at -e line 1.
Can't use an undefined value as a symbol reference at -e line 1.

##</code><code>##

$ perl -wle 'use constant OUT => "foo";print OUT'
foo