fields_reference. Reference on object's fields[3.4.5]
Retuns special referencing hash, directly linked to the object fields. When you add, delete, or modify hash elements, the same changes will occur with the referenced object's fields. And vice versa, changes in the fields of the object are reflected in the referencing hash. The referencing hash also differs from the regular one by the absence of $_default.
Note: usage of ^reflection:fields_reference[$o]to get object's fields list is more effective then^reflection:fields[$o]and^hash::create[$o].