$ > fred
$ cp fred not_a_real_dir/
cp: cannot create regular file 'not_a_real_dir/': Not a directory
$ mkdir not_a_real_dir/
$ cp fred not_a_real_dir/
$ 

##</code><code>##

$ perl -wE 'my $x; say $x ne "" ? 1 : 0'
Use of uninitialized value $x in string ne at -e line 1.
0
$ perl -wE 'my $x = ""; say $x ne "" ? 1 : 0'
0
$