($a, $b) = ($b, $a);

($a, $b, $c) = ($b, $c, $a);

my $str = 'abcd';
my @chars = split //, $str;

unless(condition){
#do something
}

if(condition){
#...
}
else{
#do something
}

if(-e file){
#read file
}
else{
die"file not exists!\n" ;
}

unless(-e file){
print"file not exists!\n" ;
}

chdir'/usr/spool/news' or die"Can't cd to spool: $!\n"

my $text = do {local $/; <$XML>};

sysread $fh, $text, -s $fh;

use Perl6::Slurp;

sub test {
# Slurp file by name

my $xml_file = 'EJV.xml';
my $text = slurp $xml_file;
print $text, "\n";

# Slurp file by handle

my $xml_file = 'EJV.xml';
open my $XML, '<', $xml_file or die $!;
my $text = slurp $XML;
print $text, "\n";
}

sub bar {
    return @{ shift() };
    #return @{ +shift };
}

调用
sub test {
    my @a = (1, 2, 3);
    my @bar = bar(\@a);
}