my %test;
$test{a} = 1;
$test{b} = 2;

##</code><code>##

something(%test);

##</code><code>##

something(a, 1, b, 2);

##</code><code>##

%test = (a, 1, b, 2);

##</code><code>##

%test = (a => 1, b => 2);

##</code><code>##

something(%test); # is like something(a, 1, b, 2);

##</code><code>##

my %hash = @_; # is like %hash = (a, 1, b, 2);