Message-ID: <d4a5d8fd-cb3a-4615-a44e-b45a5557d350@dunslane.net>
Date: Mon, 13 Oct 2025 10:58:30 -0400
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Subject: Re: add function argument name to substring and substr
To: jian he <jian.universality@gmail.com>,
 "David G. Johnston" <david.g.johnston@gmail.com>
Cc: Marcos Pegoraro <marcos@f10.com.br>,
 PostgreSQL-development <pgsql-hackers@postgresql.org>
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From: Andrew Dunstan <andrew@dunslane.net>
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On 2025-10-13 Mo 10:22 AM, jian he wrote:
> On Mon, Jul 21, 2025 at 2:31 PM jian he <jian.universality@gmail.com> wrote:
>> actually,
>> section (9.7.3.)
>> https://www.postgresql.org/docs/current/functions-matching.html#FUNCTIONS-POSIX-REGEXP
>> already have example, like:
>> substring('foobar' from 'o(.)b')
>>
>> new patch attached, split substr, substring to make review more easier.
>> v6-0001: add function argument name to function substr
>> v6-0002: add function argument name to function substring
>>
>> v6-0002 incorporated some of the changes in v5-0002-v3-delta.patch.
>> some of the changes in v5-0002-v3-delta.patch are not related to this thread,
>> so I didn't incorporate them, right now.
> hi.
>
> rebased.


I'm late to the party on this, but I wonder if it wouldn't be better to 
use a type-neutral parameter name here, like "source", which could cover 
all these cases, instead of "string", "bytes", etc.


cheers


andrew

--
Andrew Dunstan
EDB: https://www.enterprisedb.com