Re: patch (for 9.1) string functions

Robert Haas <robertmhaas@gmail.com>

From: Robert Haas <robertmhaas@gmail.com>
To: Pavel Stehule <pavel.stehule@gmail.com>
Cc: Merlin Moncure <mmoncure@gmail.com>, Itagaki Takahiro <itagaki.takahiro@gmail.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>, Erik Rijkers <er@xs4all.nl>
Date: 2010-07-26T19:07:08Z
Lists: pgsql-hackers
On Mon, Jul 26, 2010 at 2:09 PM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
> I understand, but with only text accepting, then CONCAT will has much
> less benefit - you can't do a numeric list, for example
>
> see concat(c1::text, ',', c2::text, ',' ...)
>
> with this is much simpler use a pipes '' || c1 || ',' || c2 ... and
> this operator does necessary cast self.
>
> This function is probably one use case of exception from our rules.

At least two, right?  Because for that use case you'd probably want
concat_ws().  In fact, it's hard for me to think of a variadic text
function where you wouldn't want the "no casts" behavior you're
getting via ANY.

-- 
Robert Haas
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