shift用法:
#!/usr/bin/perl sub check_required_items { my $who = shift; print "$who\n"; my %who_items = map {$_, 1} @_; my @required = qw(preserver sunserver water_bottle jacket); for my $item (@required) { unless ($who_items{$item}) { print "$who is missing $item.\n"; } } } my @gilligan = qw(red_shirt hat luc water_bottle); check_required_items('gilligan',@gilligan);
输入结果:
gilligan
gilligan is missing preserver.
gilligan is missing sunserver.
gilligan is missing jacket.
shift 取数组中第一个变量,并在列表中剔除变量,有点像pop;