Both ways are ok.
$_[0] is actually
a reference (thanks,
tye!) an alias to the first argument passed by the caller. You can evaluate (or operate on)
$_[0] directly. Passing arguments as references just adds another level of indirection.
You can also use prototypes for your subs and access your arguments inside the sub as references:
#!/usr/bin/perl
sub foo(\@\$) {
warn "foo args: (".join(",",map{"'$_'"}@_).")\n";
print "1st argument = $_[0]; content =("
. join(',',map{"'$_'"} @{$_[0]}).")\n";
print "2nd argument = $_[1]; content = '".${$_[1]}."'\n";
my ($array,$scalar) = @_;
push @$array, $$scalar;
$$scalar = "blurf";
}
my @ary = qw(foo bar baz);
my $foo = "blah";
foo(@ary,$foo);
print "ary: (@ary)\n";
print "foo: $foo\n";
output:
foo args: ('ARRAY(0x8167870)','SCALAR(0x8167978)')
1st argument = ARRAY(0x8167870); content =('foo','bar','baz')
2nd argument = SCALAR(0x8167978); content = 'blah'
ary: (foo bar baz blah)
foo: blurf
--shmem
_($_=" "x(1<<5)."?\n".q·/)Oo. G°\ /
/\_¯/(q /
---------------------------- \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}
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