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Date: Tue, 30 Apr 2019 13:44:32 +0800
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Subject: RE: [PHP-DEV] TCO: Tail Call Optimization
From: me@jhdxr.com (=?utf-8?b?Q0hVIFpoYW93ZWk=?=)

Hi David,

TCO modifies the call stack, which means features relying on it are not =
reliable any more, e.g. debug_backtrace,  stack trace of an exception, =
etc. As a result, ES6 only ask to enable TCO in strict mode, which =
dropped support for func.arguments and func.caller. PHP don't have =
similar concept yet. In addition, if you check the compatibility for =
TCO, you will realize only safari provides support for it now.


Regards,
CHU Zhaowei

=20
> -----Original Message-----
> From: David Rodrigues <david.proweb@gmail.com>
> Sent: Sunday, April 28, 2019 2:48 AM
> To: PHP Internals <internals@lists.php.net>
> Subject: [PHP-DEV] TCO: Tail Call Optimization
>=20
> Not long ago I heard about the Tail Call Optimization from ES6. It =
seemed
> obscure to me at first, but once I understood the benefit of having =
it, it
> seemed like a good idea of optimization for PHP to avoid recursion =
problems.
>=20
> Is there any plan to make it possible in the engine?
> --
> David Rodrigues