Hi,
I have an OO method which should return/set a value stored in one hash of the object (not the blessed object hash). In order to have multiple ways to do it I'm using :lvalue to allow the assignment of a value to the method call, i.e.: 
$obj->header('My Header', 'value');   # Set 
$obj->header('My Header') = 'value';  # Set
if ($obj->header('My Header') eq 'value' ) {  # Get
...

[download]
Know the overkill: When the method is called without an argument (except $self) it should return the internal header hash as ref, as rvalue would be enough.

I know the return statement must be omitted in order to make lvalue work. Because subs return then the return value of the last statement I thought I just put the two different return values at the end of a if () { } else { } statement. This returns an error message (Can't return a temporary from lvalue subroutine), so I put in a return statement for the hash ref.
Now it's working: lvalue for hash element, rvalue for whole hash. The code looks like this: 

sub header : lvalue {
    my ( $self, $h, $value ) = @_;

    if ( @_ == 1 ) {
        return $self->{header};
    }
    $self->{header}->{$h} = $value
      if defined $value;
    $self->{header}->{$h};
}

[download]
My question now: Is this clean enough or already a dirty trick or "black magic"? I would love to hear the opinion from a Perl guru with deeper insight in lvalue subs.

Thanks

In reply to Mixed lvalue/rvalue sub function by mscharrer

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