$ perl -we'require Data::Dumper;  print Dumper $^O'
Name "main::Dumper" used only once: possible typo at -e line 1.
print() on unopened filehandle Dumper at -e line 1.

##</code><code>##

$ perl -we'use Data::Dumper;  print Dumper $^O'
$VAR1 = 'cygwin';