Replace "use-by-ref" by static vars when possible in closures

Author: nicolas-grekas

AbstractUnicodeString.php

@@ -155,7 +155,9 @@ public function ascii(array $rules = []): self
     public function camel(): static
     {
         $str = clone $this;
-        $str->string = str_replace(' ', '', preg_replace_callback('/\b.(?![A-Z]{2,})/u', static function ($m) use (&$i) {
+        $str->string = str_replace(' ', '', preg_replace_callback('/\b.(?![A-Z]{2,})/u', static function ($m) {
+            static $i = 0;
+
             return 1 === ++$i ? ('İ' === $m[0] ? 'i̇' : mb_strtolower($m[0], 'UTF-8')) : mb_convert_case($m[0], \MB_CASE_TITLE, 'UTF-8');
         }, preg_replace('/[^\pL0-9]++/u', ' ', $this->string)));
 

LazyString.php

@@ -30,7 +30,9 @@ public static function fromCallable(callable|array $callback, mixed ...$argument
         }
 
         $lazyString = new static();
-        $lazyString->value = static function () use (&$callback, &$arguments, &$value): string {
+        $lazyString->value = static function () use (&$callback, &$arguments): string {
+            static $value;
+
             if (null !== $arguments) {
                 if (!\is_callable($callback)) {
                     $callback[0] = $callback[0]();