Re: patch (for 9.1) string functions

Pavel Stehule <pavel.stehule@gmail.com>

From: Pavel Stehule <pavel.stehule@gmail.com>
To: Robert Haas <robertmhaas@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: 2010-07-27T06:22:54Z
Lists: pgsql-hackers
2010/7/26 Robert Haas <robertmhaas@gmail.com>:
> 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().

sorry, yes

Pavel

 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
> EnterpriseDB: http://www.enterprisedb.com
> The Enterprise Postgres Company
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