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diff --git a/Userland/Libraries/LibJS/Runtime/Accessor.h b/Userland/Libraries/LibJS/Runtime/Accessor.h
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+++ b/Userland/Libraries/LibJS/Runtime/Accessor.h
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+/*
+ * Copyright (c) 2020, Matthew Olsson <matthewcolsson@gmail.com>
+ * Copyright (c) 2020, Linus Groh <mail@linusgroh.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include <LibJS/Runtime/Function.h>
+#include <LibJS/Runtime/VM.h>
+
+namespace JS {
+
+class Accessor final : public Cell {
+public:
+    static Accessor* create(VM& vm, Function* getter, Function* setter)
+    {
+        return vm.heap().allocate_without_global_object<Accessor>(getter, setter);
+    }
+
+    Accessor(Function* getter, Function* setter)
+        : m_getter(getter)
+        , m_setter(setter)
+    {
+    }
+
+    Function* getter() const { return m_getter; }
+    void set_getter(Function* getter) { m_getter = getter; }
+
+    Function* setter() const { return m_setter; }
+    void set_setter(Function* setter) { m_setter = setter; }
+
+    Value call_getter(Value this_value)
+    {
+        if (!m_getter)
+            return js_undefined();
+        return vm().call(*m_getter, this_value);
+    }
+
+    void call_setter(Value this_value, Value setter_value)
+    {
+        if (!m_setter)
+            return;
+        // FIXME: It might be nice if we had a way to communicate to our caller if an exception happened after this.
+        [[maybe_unused]] auto rc = vm().call(*m_setter, this_value, setter_value);
+    }
+
+    void visit_edges(Cell::Visitor& visitor) override
+    {
+        visitor.visit(m_getter);
+        visitor.visit(m_setter);
+    }
+
+private:
+    const char* class_name() const override { return "Accessor"; };
+
+    Function* m_getter { nullptr };
+    Function* m_setter { nullptr };
+};
+
+}