diff --git a/src/Faker/Documentor.php b/src/Faker/Documentor.php
index 1877c1c3..0cfa930c 100644
--- a/src/Faker/Documentor.php
+++ b/src/Faker/Documentor.php
@@ -42,6 +42,8 @@ class Documentor
                     $example = "array('". join("', '", $example) . "')";
                 } elseif ($example instanceof \DateTime) {
                     $example = "DateTime('" . $example->format('Y-m-d H:i:s') . "')";
+                } elseif ($example instanceof Generator || $example instanceof UniqueGenerator) { // modifier
+                    $example = '';
                 } else {
                     $example = var_export($example, true);
                 }
diff --git a/src/Faker/Provider/Image.php b/src/Faker/Provider/Image.php
index 153e2d92..651cf806 100644
--- a/src/Faker/Provider/Image.php
+++ b/src/Faker/Provider/Image.php
@@ -37,7 +37,7 @@ class Image extends Base
      *
      * @example '/path/to/dir/13b73edae8443990be1aa8f1a483bc27.jpg'
      */
-    public static function image($dir, $width = 640, $height = 480, $category = null)
+    public static function image($dir = '/tmp', $width = 640, $height = 480, $category = null)
     {
         // Validate directory path
         if (!is_dir($dir) || !is_writable($dir)) {