update code for PHP 8

Author: drupol

src/ChunkIterableAggregate.php

@@ -45,7 +45,7 @@ public function getIterator(): Generator
     {
         $values = [];
 
-        foreach ($this->iterable as $key => $value) {
+        foreach ($this->iterable as $value) {
             if (count($values) !== $this->chunkSize) {
                 $values[] = $value;
 

src/ClosureIterator.php

@@ -11,7 +11,6 @@
 
 use Generator;
 use Iterator;
-use ReturnTypeWillChange;
 
 /**
  * @template TKey
@@ -50,17 +49,15 @@ public function __construct(callable $callable, iterable $parameters = [])
     /**
      * @return T
      */
-    #[ReturnTypeWillChange]
-    public function current()
+    public function current(): mixed
     {
         return $this->generator->current();
     }
 
     /**
      * @return TKey
      */
-    #[ReturnTypeWillChange]
-    public function key()
+    public function key(): mixed
     {
         return $this->generator->key();
     }

src/IterableIterator.php

@@ -11,7 +11,6 @@
 
 use Generator;
 use Iterator;
-use ReturnTypeWillChange;
 
 /**
  * @template TKey
@@ -45,17 +44,15 @@ public function __construct(iterable $iterable)
     /**
      * @return T
      */
-    #[ReturnTypeWillChange]
-    public function current()
+    public function current(): mixed
     {
         return $this->iterator->current();
     }
 
     /**
      * @return TKey
      */
-    #[ReturnTypeWillChange]
-    public function key()
+    public function key(): mixed
     {
         return $this->iterator->key();
     }

src/ReductionIterableAggregate.php

@@ -30,7 +30,7 @@ final class ReductionIterableAggregate implements IteratorAggregate
     /**
      * @var W
      */
-    private $initial;
+    private mixed $initial;
 
     /**
      * @var iterable<TKey, T>
@@ -42,7 +42,7 @@ final class ReductionIterableAggregate implements IteratorAggregate
      * @param (Closure(W, T, TKey, iterable<TKey, T>): W) $closure
      * @param W $initial
      */
-    public function __construct(iterable $iterable, Closure $closure, $initial)
+    public function __construct(iterable $iterable, Closure $closure, mixed $initial)
     {
         $this->iterable = $iterable;
         $this->closure = $closure;

src/TypedIterableAggregate.php

@@ -44,10 +44,7 @@ public function __construct(iterable $iterable, ?callable $getType = null)
         $this->iterable = $iterable;
 
         $this->getType = $getType ??
-            /**
-             * @param mixed $variable
-             */
-            static function ($variable): string {
+            static function (mixed $variable): string {
                 if (!is_object($variable)) {
                     return gettype($variable);
                 }