C:\Perl>type MyFoo.pm package MyFoo; use strict; use warnings; sub bar {print "bar\n"} #1; C:\Perl>type foo.pl use warnings; use strict; use MyFoo; print "hello\n"; MyFoo::bar(); C:\Perl>perl foo.pl MyFoo.pm did not return a true value at foo.pl line 3. BEGIN failed--compilation aborted at foo.pl line 3.