my %hash = ('key1' => 'v1', 'key2' => 'v2');

del_hash_key(\%hash);

sub del_hash_key {
	my $params = shift;
	my %hash = %$params;
	delete $hash{'key1'};
	print %hash; # Prints the latter key/value pair
	print "\n";
}

print %hash; # Prints both key/value pairs