1package Some::Module; 2use strict; 3use warnings; 4use base qw(Exporter); 5 6our @EXPORT_OK = qw(some_sub); 7 8# This is an example of a subroutine that returns (undef, $msg) 9# to signal failure. 10 11sub some_sub { 12 my ($arg) = @_; 13 14 if ($arg) { 15 return (undef, "Insufficient credit"); 16 } 17 18 return (1,2,3); 19} 20 211; 22