Hi, I have a linked list object: 
{
    rest => $next_node,
    first => $data
}

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and a value() method that converts the linked list to a perl list: 
sub value {
    my ($self) = @_;
    my @value = ($self->{first},
                 $self->{rest} ? $self->{rest}->value : ());
    return @value;
}

[download]
The reason I need the temporary @value is that sometimes value() gets called in a scalar context in which case it should return the length of the list, but if I was to just write 
sub value {
    my ($self) = @_;
    return ($self->{first},
            $self->{rest} ? $self->{rest}->value : ())
}

[download]
then in a scalar context the "," gets interpreted as the comma operator and the lhs of the comma gets thrown away, recursively, so the result is always zero.

I guess I could also write: 

sub value {
    my ($self) = @_;
    return @{[$self->{first},
              $self->{rest} ? $self->{rest}->value : ()]};
}

[download]
but neither solution seems totally satisfying.

Am I missing something?

In reply to enforcing list context by billh

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