# functionally speaking, this....
%hash = ('a' => 1, 'b' => 2, 'c' => 3);
myfunc(%hash);

# is the same as this...
myfunc('a', 1, 'b', 2, 'c', 3);

##</code><code>##

$scalar = 'blue';
%hash = ('a' => 1, 'b' => 2);
myfunc($scalar, %hash);

sub myfunc {
  my $scalar = shift;
  my %hash = @_;
  print $hash{'a'};
}

##</code><code>##

%hash = ('a' => 1, 'b' => 2);
$scalar = 'blue';
myfunc(\%hash, $scalar);

sub myfunc {
  my($hashref,$scalar) = @_;
  print $hashref->{'a'};
}