##
sub say {
my ( $x, %param ) = @_;
# ...
}
&say( "Hello", name => "world" );
##
##
sub bar {
my ( @a, @b ) = @_; # wrong!
# ...
}
&bar( @array1, @array2 ); # wrong!
##
##
sub bar {
my ( $a_ref, $b_ref ) = @_; # ok
# ...
}
&bar( \@array1, \@array2 ); # ok