#!perl use strict; use warnings; $|++; my $first; my @sec; print &compose, "\n"; $first = 'UNO'; print &compose,"\n"; push @sec, '1','2'; print &compose,"\n"; $sec[5] = 'sixt'; print &compose,"\n"; undef $first ; @sec = (); print &compose,"\n"; sub compose { my $it = 'First is '. ($first ? $first : 'not yet defined '). ' and the list is '. (@sec ? '('.(join ' ',map {$_||'UNDEFINED'}@sec ).')': ' empty'); return $it; } __OUTPUT__ First is not yet defined and the list is empty First is UNO and the list is empty First is UNO and the list is (1 2) First is UNO and the list is (1 2 UNDEFINED UNDEFINED UNDEFINED sixt) First is not yet defined and the list is empty