diff --git a/Test/Unit/Visitor/Asserter.php b/Test/Unit/Visitor/Asserter.php
index 65b9087..c6defc2 100644
--- a/Test/Unit/Visitor/Asserter.php
+++ b/Test/Unit/Visitor/Asserter.php
@@ -36,6 +36,7 @@
 
 namespace Hoa\Ruler\Test\Unit\Visitor;
 
+use ArrayObject;
 use Hoa\Ruler as LUT;
 use Hoa\Ruler\Visitor\Asserter as SUT;
 use Hoa\Test;
@@ -591,6 +592,51 @@ function ($x) {
                     ->isIdenticalTo($result);
     }
 
+    public function case_visit_operator_array_like_dimension_1()
+    {
+        $this
+            ->given(
+                $operator = new LUT\Model\Operator('c', [7]),
+                $operator->index('x'),
+                $asserter = new SUT(),
+                $asserter->setOperator(
+                    'c',
+                    function ($x) {
+                        return new ArrayObject(['x' => $x * 6]);
+                    }
+                )
+            )
+            ->when($result = $this->invoke($asserter)->visitOperator($operator))
+            ->then
+                ->integer($result)
+                    ->isEqualTo(42)
+                ->integer($asserter->visit($operator))
+                    ->isIdenticalTo($result);
+    }
+
+    public function case_visit_operator_array_like_dimension_2()
+    {
+        $this
+            ->given(
+                $operator = new LUT\Model\Operator('c', [7]),
+                $operator->index('x'),
+                $operator->index('y'),
+                $asserter = new SUT(),
+                $asserter->setOperator(
+                    'c',
+                    function ($x) {
+                        return new ArrayObject(['x' => new ArrayObject(['y' => $x * 6])]);
+                    }
+                )
+            )
+            ->when($result = $this->invoke($asserter)->visitOperator($operator))
+            ->then
+                ->integer($result)
+                    ->isEqualTo(42)
+                ->integer($asserter->visit($operator))
+                    ->isIdenticalTo($result);
+    }
+
     public function case_visit_operator_array_dimension_1_undefined_index()
     {
         $this
@@ -643,6 +689,32 @@ function ($x) {
                 ->hasMessage('Try to access to an undefined index: y (dimension number 1 of c()), because it is not an array.');
     }
 
+    public function case_visit_operator_array_like_dimension_1_undefined_index()
+    {
+        $this
+            ->given(
+                $operator = new LUT\Model\Operator('c', [7]),
+                $operator->index('z'),
+                $asserter = new SUT(),
+                $asserter->setOperator(
+                    'c',
+                    function ($x) {
+                        return new ArrayObject(['x' => 42]);
+                    }
+                )
+            )
+            ->exception(function () use ($asserter, $operator) {
+                $this->invoke($asserter)->visitOperator($operator);
+            })
+                ->isInstanceOf(LUT\Exception\Asserter::class)
+                ->hasMessage('Try to access to an undefined index: z (dimension number 1 of c()).')
+            ->exception(function () use ($asserter, $operator) {
+                $asserter->visit($operator);
+            })
+                ->isInstanceOf(LUT\Exception\Asserter::class)
+                ->hasMessage('Try to access to an undefined index: z (dimension number 1 of c()).');
+    }
+
     public function case_visit_operator_attribute_dimension_1()
     {
         $this
diff --git a/Visitor/Asserter.php b/Visitor/Asserter.php
index ca15d60..1840d39 100644
--- a/Visitor/Asserter.php
+++ b/Visitor/Asserter.php
@@ -36,6 +36,7 @@
 
 namespace Hoa\Ruler\Visitor;
 
+use ArrayAccess;
 use Hoa\Consistency;
 use Hoa\Ruler;
 use Hoa\Visitor;
@@ -341,7 +342,10 @@ protected function visitArrayDimension(
         $value = $dimension[Ruler\Model\Bag\Context::ACCESS_VALUE];
         $key   = $value->accept($this, $handle, $eldnah);
 
-        if (!is_array($contextPointer)) {
+        $isArray     = is_array($contextPointer);
+        $isArrayLike = !$isArray && $contextPointer instanceof ArrayAccess;
+
+        if (false === $isArray && false === $isArrayLike) {
             throw new Ruler\Exception\Asserter(
                 'Try to access to an undefined index: %s ' .
                 '(dimension number %d of %s), because it is ' .
@@ -351,7 +355,8 @@ protected function visitArrayDimension(
             );
         }
 
-        if (false === array_key_exists($key, $contextPointer)) {
+        if ((true === $isArray     && false === array_key_exists($key, $contextPointer)) ||
+            (true === $isArrayLike && false === $contextPointer->offsetExists($key))) {
             throw new Ruler\Exception\Asserter(
                 'Try to access to an undefined index: %s ' .
                 '(dimension number %d of %s).',