Arbitrary static variable initializers

[thekid]

Support https://wiki.php.net/rfc/arbitrary_static_variable_initializers natively in PHP 8.3 emitter.

---

Currently, this functionality is emulated by using the following, see implementation status:

use util\Date;

// What gets written
function start() {
  static $now= new Date();

  var_dump($now);
}

// What is emitted
function start() {
  static $now; $now??= new Date();

  var_dump($now);
}

[thekid]

RFC has been accepted, now need to wait for php/php-src#9301 to be merged before being to change PHP 8.3 emitter to emit native code for this.

[thekid]

Merged in php/php-src@0b1d750

[thekid]

Updated https://github.com/xp-framework/compiler/wiki/Implementation-status

[thekid]

Released in https://github.com/xp-framework/compiler/releases/tag/v8.14.0