RETURNING syntax for COPY

Hello,
as a continuation of my proposal expanding RETURNING syntax by
AFTER/BEFORE, there can be enough time to implement RETURNING for COPY.
I'd like to hear your opinion on that. My draft idea is:
COPY FROM ... RETURNING table_name.* -> returns all values copied to
table after all triggers invoke
COPY FROM ... RETURNING BEFORE.* -> returns all values copied to table
before triggers (all raw values from file)
COPY TO ... RETURNING table_name.* -> returns all values from table
COPY TO ... RETURNING AFTER.*/BEFORE.* -> the same
What do you think about?
Regards,
Karol Trzcionka