grouping treated as keyword in function return table

Postgres 9.5.3 built from source.  However, I think this has been
happening for a long time.

create function a() returns table( grouping integer ) language sql as $$
select 1;
$$;
ERROR:  syntax error at or near "grouping"
LINE 1: create function a() returns table( grouping integer ) langua...

If we quote "grouping"
                                            ^
create function a() returns table( "grouping" integer ) language sql as $$
select 1;
$$
;
CREATE FUNCTION

grouping is a valid column in a table and does not need to be quoted:

create temp table test( grouping integer );
CREATE TABLE

So, in almost all cases grouping is not required to be quoted,
however when used in a table defined as a function return type, it
is.  Additionally, pg_dumpall does not quote grouping when dumping
the function so the function will not be restored when the dump is
loaded.

Thanks,

Mike

-
Mike Porter
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