On Mon, Jul 26, 2010 at 3:49 PM, Merlin Moncure <mmoncure@gmail.com> wrote:
> concat() is not a variadic text function. it is variadic "any" that
> happens to do text coercion (not casting) inside the function. The
> the assumption that concat is casting internally is probably wrong.
> Suppose I had hacked the int->text cast to call a custom function -- I
> would very much expect concat() not to produce output from that
> function, just the vanilla output text (I could always force the cast
> if I wanted to).
>
> concat is just a function that does something highly similar to
> casting. suppose I had a function count_memory(variadic "any") that
> summed memory usage of input args -- forcing casts would make no sense
> in that context (I'm not suggesting that you think so -- just bringing
> up a case that illustrates how forcing cast into the function can
> change behavior in subtle ways).
Right, but I already said I wasn't objecting to the use of variadic
ANY in cases like that - only in cases where, as here, you were
basically taking any old arguments and forcing them all to text.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise Postgres Company
