you can also have the first parameter control whether to interpret the rest of @_ as @_ or $_[0] as a hashref, for example,

sub func {
    my($param1, $param2, $param3) = @_;
    my $tempparam1;
    if(ref($param1) eq "HASH") {
        $tempparam1  = $param1->{'param1'};
        $param2      = $param1->{'param2'};
        $param3      = $param1->{'param3'};
        $param1      = $tempparam1;
    }
    print "param1 is $param1 param2 is $param2 param3 is $param3 \n";
}
func( 'one', 'two', 'three');
func( {param1 => 'one', param2 => 'two', param3 => 'three'});
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I've seen the above in Perl. Offers users TIMTOWTDI.