diff --git a/docs/examples.md b/docs/examples.md
index 3fff520..ccb4ae6 100644
--- a/docs/examples.md
+++ b/docs/examples.md
@@ -1347,7 +1347,7 @@ foreach ($array as $key => $value) {
 ```php
 <?php
 /**
- * @phpstan-param callable(TValue, TKey $key=):void $callback
+ * @phpstan-param callable(TValue, TKey $key):void $callback
  * @phpstan-return AssocValue<TKey, TValue>
  */
 public function each(callable $callback): AssocValue;
@@ -1391,7 +1391,7 @@ public function filterEmpty(): AssocValue;
 <?php
 /**
  * @template TNewValue
- * @param callable(TValue,TKey $key=):TNewValue $transformer
+ * @param callable(TValue,TKey $key):TNewValue $transformer
  * @phpstan-return AssocValue<TKey, TNewValue>
  */
 public function map(callable $transformer): AssocValue;
@@ -1532,7 +1532,7 @@ public function values(): ArrayValue;
 <?php
 /**
  * @template TNewKey of int|string
- * @phpstan-param callable(TKey $key, TValue $value=): TNewKey $transformer
+ * @phpstan-param callable(TKey $key, TValue $value): TNewKey $transformer
  * @phpstan-return AssocValue<TNewKey, TValue>
  */
 public function mapKeys(callable $transformer): AssocValue;
@@ -3916,7 +3916,7 @@ array (
 <?php
 /**
  * @template TNewValue
- * @param callable(TValue,TKey $key=):TNewValue $transformer
+ * @param callable(TValue,TKey $key):TNewValue $transformer
  * @phpstan-return IterableValue<TKey, TNewValue>
  */
 public function map(callable $transformer): IterableValue;
diff --git a/src/AssocArray.php b/src/AssocArray.php
index d87b424..b8ff799 100644
--- a/src/AssocArray.php
+++ b/src/AssocArray.php
@@ -49,7 +49,7 @@ public function __construct($items)
 
     /**
      * @template TNewValue
-     * @phpstan-param callable(TValue $value, TKey $key=):TNewValue $transformer
+     * @phpstan-param callable(TValue $value, TKey $key):TNewValue $transformer
      * @phpstan-return AssocArray<TKey, TNewValue>
      */
     public function map(callable $transformer): AssocArray
@@ -67,7 +67,7 @@ public function keys(): ArrayValue
 
     /**
      * @template TNewKey of int|string
-     * @param callable(TKey $key, TValue $value=): TNewKey $transformer
+     * @param callable(TKey $key, TValue $value): TNewKey $transformer
      * @phpstan-return AssocArray<TNewKey, TValue>
      */
     public function mapKeys(callable $transformer): AssocArray
@@ -127,7 +127,7 @@ public function sortKeys(callable $comparator): AssocArray
     }
 
     /**
-     * @phpstan-param callable(TValue $value, TKey $key=):void $callback
+     * @phpstan-param callable(TValue $value, TKey $key):void $callback
      * @phpstan-return AssocArray<TKey, TValue>
      */
     public function each(callable $callback): AssocArray
diff --git a/src/AssocValue.php b/src/AssocValue.php
index 682b24e..d8ee0c0 100644
--- a/src/AssocValue.php
+++ b/src/AssocValue.php
@@ -17,7 +17,7 @@
 interface AssocValue extends Value, Collection, IteratorAggregate, ArrayAccess, Associable
 {
     /**
-     * @phpstan-param callable(TValue, TKey $key=):void $callback
+     * @phpstan-param callable(TValue, TKey $key):void $callback
      * @phpstan-return AssocValue<TKey, TValue>
      */
     public function each(callable $callback): AssocValue;
@@ -41,7 +41,7 @@ public function filterEmpty(): AssocValue;
 
     /**
      * @template TNewValue
-     * @param callable(TValue,TKey $key=):TNewValue $transformer
+     * @param callable(TValue,TKey $key):TNewValue $transformer
      * @phpstan-return AssocValue<TKey, TNewValue>
      */
     public function map(callable $transformer): AssocValue;
@@ -107,7 +107,7 @@ public function values(): ArrayValue;
 
     /**
      * @template TNewKey of int|string
-     * @phpstan-param callable(TKey $key, TValue $value=): TNewKey $transformer
+     * @phpstan-param callable(TKey $key, TValue $value): TNewKey $transformer
      * @phpstan-return AssocValue<TNewKey, TValue>
      */
     public function mapKeys(callable $transformer): AssocValue;
diff --git a/src/Associable/Map.php b/src/Associable/Map.php
index 04caedc..d017e7f 100644
--- a/src/Associable/Map.php
+++ b/src/Associable/Map.php
@@ -14,12 +14,12 @@ final class Map implements Associable
 {
     /** @var Associable<TKey,TValue> */
     private Associable $associable;
-    /** @var callable(TValue $value, TKey $key=):TNewValue */
+    /** @var callable(TValue $value, TKey $key):TNewValue */
     private $transformer;
 
     /**
      * @param Associable<TKey,TValue> $associable
-     * @param callable(TValue $value, TKey $key=):TNewValue $transformer
+     * @param callable(TValue $value, TKey $key):TNewValue $transformer
      */
     public function __construct(Associable $associable, callable $transformer)
     {
diff --git a/src/Associable/MapKeys.php b/src/Associable/MapKeys.php
index a2a2311..db53de8 100644
--- a/src/Associable/MapKeys.php
+++ b/src/Associable/MapKeys.php
@@ -14,12 +14,12 @@ final class MapKeys implements Associable
 {
     /** @var Associable<TKey,TValue> */
     private Associable $associable;
-    /** @var callable(TKey $key, TValue $value=):TNewKey */
+    /** @var callable(TKey $key, TValue $value):TNewKey */
     private $transformer;
 
     /**
      * @param Associable<TKey,TValue> $associable
-     * @param callable(TKey $key, TValue $value=):TNewKey $transformer
+     * @param callable(TKey $key, TValue $value):TNewKey $transformer
      */
     public function __construct(Associable $associable, callable $transformer)
     {
diff --git a/src/InfiniteIterableValue.php b/src/InfiniteIterableValue.php
index 51296f2..931c6cc 100644
--- a/src/InfiniteIterableValue.php
+++ b/src/InfiniteIterableValue.php
@@ -122,7 +122,7 @@ public function filterEmpty(): InfiniteIterableValue
 
     /**
      * @template TNewValue
-     * @param callable(TValue,TKey $key=):TNewValue $transformer
+     * @param callable(TValue,TKey $key):TNewValue $transformer
      * @phpstan-return InfiniteIterableValue<TKey, TNewValue>
      */
     public function map(callable $transformer): InfiniteIterableValue
diff --git a/src/IterableValue.php b/src/IterableValue.php
index a3f4704..7e0fafb 100644
--- a/src/IterableValue.php
+++ b/src/IterableValue.php
@@ -33,7 +33,7 @@ public function filterEmpty(): IterableValue;
 
     /**
      * @template TNewValue
-     * @param callable(TValue,TKey $key=):TNewValue $transformer
+     * @param callable(TValue,TKey $key):TNewValue $transformer
      * @phpstan-return IterableValue<TKey, TNewValue>
      */
     public function map(callable $transformer): IterableValue;