You could use prototypes (see perlsub, caveats here). Consider:

#!/usr/bin/perl

sub getInfo ($\%) {
    my $scalar = shift;
    my $hash = shift;
    print "scalar = '$scalar'\n";
    print "hash = $hash\n";
    print "$_ => $hash->{$_}\n" for keys %$hash;
}   

my %hash = (foo => 'bar', baz => 'quux');
my $scalar = 'string';

getInfo($scalar,%hash);
__END__
[download]

output:

scalar = 'string'
hash = HASH(0x81677a4)
baz => quux
foo => bar
[download]

This has the advantage of throwing an error at compile time if the wrong arguments are passed in:

my @array = qw(foo bar baz);
getInfo($scalar, @array);

Type of arg 2 to main::getInfo must be hash (not private array) at foo
+.pl line 16, near "@array)"
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--shmem

you mean Passing, not Parsing :-)

update: inserted "You could" and caveat :-)

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}