diff --git a/src/Assert.php b/src/Assert.php
index a03e2a2..f82ee5b 100644
--- a/src/Assert.php
+++ b/src/Assert.php
@@ -548,7 +548,7 @@ public static function isInstanceOfAny(mixed $value, mixed $classes, string $mes
         static::reportInvalidArgument(\sprintf(
             $message ?: 'Expected an instance of any of %2$s. Got: %s',
             static::typeToString($value),
-            \implode(', ', \array_map([static::class, 'valueToString'], \iterator_to_array($classes)))
+            \implode(', ', \array_map(static::valueToString(...), \iterator_to_array($classes)))
         ));
     }
 
@@ -1072,7 +1072,7 @@ public static function inArray(mixed $value, mixed $values, string $message = ''
             static::reportInvalidArgument(\sprintf(
                 $message ?: 'Expected one of: %2$s. Got: %s',
                 static::valueToString($value),
-                \implode(', ', \array_map([static::class, 'valueToString'], $values))
+                \implode(', ', \array_map(static::valueToString(...), $values))
             ));
         }