use strict; use warnings; send_email ( { subject => "Test subject", body => "Test body", } ); sub send_email { my $param = shift; my $subject = $param->{subject}; my $body = $param->{body}; my $is_dev_mode = exists $param->{is_dev_mode} ? $param->{is_dev_mode} : undef; $is_dev_mode = 1 unless ( $is_dev_mode == 0 || $is_dev_mode == 1 ) ; # In case the CGI param is ''; default is to be "safe" (is_dev_mode == 1) warn "is_dev_mode is '", $is_dev_mode, "'\n"; _blast_email_to_all_my_important_customers( $subject, $body ) unless ( $is_dev_mode ); }