diff --git a/src/EnvReader/GenericConfig.php b/src/EnvReader/GenericConfig.php
index f900c54..bedc510 100644
--- a/src/EnvReader/GenericConfig.php
+++ b/src/EnvReader/GenericConfig.php
@@ -110,7 +110,7 @@ abstract class GenericConfig {
      */
     public function getPropertyAsString (string $name, ?string $default = null): string {
         $value = $this->getProperty($name, $default);
-        if (!is_string($value) || !is_object($value) || method_exists($value, '__ToString')) {
+        if (!is_string($value) && !is_object($value) && !method_exists($value, '__ToString')) {
             throw new RangeException('The "' . $name . '" property is not a valid string : ' . $value);
         }