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 <CAPyj-LDf6exN2R15Q26+xoNu9vtuD7hu4sFvaTPbPDe4mrQCpA@mail.gmail.com> <a0973bd2-8c1d-c3b3-73a1-6909e2b72db1@gmail.com>
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Date: Tue, 14 Mar 2023 23:58:15 +0100
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To: internals@lists.php.net
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Subject: Re: [PHP-DEV] Brainstorming idea: inline syntax for lexical
 (captured) variables
From: tovilo.ilija@gmail.com (Ilija Tovilo)

> I guess you'd have to generate a new class entry every time the "new
> class" line was run, and inject the extra values into that.
>
>
> If it was limited to capturing scalars and arrays, you could treat it as
> a kind of macro expansion, i.e. this ...
>
> $example = new class {
>      public $inner = $^outer;
> }
>
> ... could be a sort of sugar for:
>
> eval(
>      sprintf(
>          'return new class {
>              public $inner = %s;
>          };',
>          var_export($outer, true)
>      )
> );
>
> Which is valid code, if not particularly efficient: https://3v4l.org/sQaUS

Unfortunately, PHP isn't really well suited for something like that.
Eval'd classes are still request-persistent, so any created object
would leak its class structure (which is much bigger and less
optimized in terms of memory than the object).

Normal anonymous classes: https://3v4l.org/41UGH
Anonymous classes created through eval (and thus creating a separate
class): https://3v4l.org/Q9eE3

Ilija