Copying contents of OLD/NEW in a trigger

I'm trying to copy the contents of old/new inside of a trigger
to pass to another function. Is there any way to do this?

I've created a %ROWTYPE variable and tried both:

------------------------------
old_row := OLD;

and

select * into old_row from old;
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The first gives a parse error, and the second gives the standard
error about using old in a non-rule query. Is there no way to do
this without copying every column one by one? I need to pass
pretty much every field of old/new to the function, and it seems
kind of absurd that I'd have to pass them all separately.

Any help would be much appreciated.

Thanks in advance,
Tim Seever