Re: RfD: more powerful "any" types

On Thu, 2009-09-10 at 08:44 +0300, Hannu Krosing wrote:

> maybe just let users say what they mean, so first time we have "any" and
> if we need more then we say "same_as(...)"

Acutually we could be even more SQL-y and have a more verbose syntax for
pseudotypes by extending the grammar

CREATE FUNCTION foo(
a ANY TYPE,
b SAME TYPE AS a,
c ANY TYPE
OUT d ARRAY OF SAME TYPE AS c
) ....

TYPE could probably be optional

> so your example becomes
>
>
> CREATE FUNCTION foo(a any, b same_type_as(a), c any)
> RETURNS same_type_as(c)[]
> AS $$
> ...
> $$;
>
> or the same using positional arguments
>
> CREATE FUNCTION foo(a any, b same_type_as(1), c any)
> RETURNS same_type_as(3)[]
> AS $$
> ...
> $$;
>
> this then gets transformed at parse time to whatever internal
> representation of type sameness we use.
>
> --
> Hannu Krosing http://www.2ndQuadrant.com
> PostgreSQL Scalability and Availability
> Services, Consulting and Training
>
>
>