Discussion

What ARRAY_REF return ?

What expected in using ARRAY_REF as the return value ? A list of PRIMARY KEY ?

How To Get All Primary Keys ?

We need to call get_next_keys() again and again to retrieve all keys. It may be useful to implement special method to return a list of keys but it is not implemented.

get_primary_keys() ? find('*', { all => 1 }) is used for this purpose. It is of no use to implement specific method for this.

HASH_REF As Return Value ?

What expected ?

RETURN VALUE = {
	KEY_1 => VALUE_1,
	KEY_2 => VALUE_2,	
}

If a mail address has several attributes, this method is useful. For example, consider digest delivery:

ADDRESS => {
	internal	=> 	3 hours,
	compression	=>	no,
	format		=>	mime/multipart,
};

Abstracted Cache IO layer is this type such as:

FML::Error -> FML::Error::Cache -> Tie::JournaledDir