proposal: better support for debugging of overloaded functions

Hello

I am missing a some unique identifier in exception info. I would to
use it in combination with \sf statement

I have a log

WARNING: NP_CPS: a cannot to build a RSLT object
DETAIL: dsql_text: SELECT * FROM
public._npacceptflatfile(order_nr:=to_number('O00000032',
'O99999999')::int,sequence_nr:=1,ref_sequence_nr:=2,recipient_op:=201,losing_op:=303)
message: cannot to identify real type for record type variable
CONTEXT: PL/pgSQL function "assign_rslts" line 50 at assignment
SQL statement "SELECT workflow.assign_rslts('2011-12-18',
'09:30:30',
to_operator := 201,
from_operator := 303)"
PL/pgSQL function "inline_code_block" line 855 at PERFORM

and I would to look on "assign_rslts" function, but
ohs=# \sf workflow.assign_rslts
ERROR: more than one function named "workflow.assign_rslts"

and I have to find a parameters and manually build a parameters list.
My proposal is enhancing l CONTEXT line about function's oid and
possibility to use this oid in \sf and \df function

some like

CONTEXT: PL/pgSQL function "assign_rslts" line 50 at assignment (oid: 65903)

...

\sf+ 65903

This simple feature can reduce a time that is necessary to identify a
bug in overloaded functions.

Other possibility is just enhancing context line to be more friendly
to \sf statement

CONTEXT: PL/pgSQL function workflow.assign_rslts(date,time without
time zone,operatorid_type,operatorid_type)"" line 50 at assignment

But this is not too readable and it implementation is harder, because
in exception time is not access to system tables - so this string
should be cached somewhere.

Notes, ideas??

Regards

Pavel Stehule