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Date: Thu, 6 Feb 2025 22:43:36 +0100
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Subject: Re: [PHP-DEV] Pattern matching details questions
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To: Larry Garfield <larry@garfieldtech.com>,
 php internals <internals@lists.php.net>
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From: cmbecker69@gmx.de ("Christoph M. Becker")

On 06.02.2025 at 20:24, Larry Garfield wrote:

> On Thu, Feb 6, 2025, at 3:05 AM, Valentin Udaltsov wrote:
>
>>> Because PHP uses only an LL(1) parser

Actually, we're using an LALR(1) parser; LL(1) is more constrained
(although, personally, I like those for their simplicity).

>> Are there any plans to upgrade the parser to bypass these limitations?
>> I remember Nikita shared some thoughts on why this is not trivial in
>> https://wiki.php.net/rfc/arrow_functions_v2. Maybe something has
>> changed since then?
>
> I'm not aware of any plans to change the parser.  That would be a rather=
 dramatic and invasive change.

There have been ideas to use some more powerful features of bison[1],
like GLR, so that would not necessarily be a drastic and invasive
change.  I'm not aware of any concrete plans, and these more powerful
features are not without downsides.

[1]
<https://www.gnu.org/software/bison/manual/html_node/LR-Table-Construction=
.html#LR-Table-Construction.>

Christoph