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diff --git a/butl/optional b/butl/optional
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+// file      : butl/optional -*- C++ -*-
+// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUTL_OPTIONAL
+#define BUTL_OPTIONAL
+
+namespace butl
+{
+  // Simple optional class template while waiting for std::optional.
+  //
+  template <typename T>
+  class optional
+  {
+  public:
+    typedef T value_type;
+
+    optional (): null_ (true) {}
+    optional (const T& v): value_ (v), null_ (false) {}
+    optional& operator= (const T& v) {value_ = v; null_ = false; return *this;}
+
+    T&       value () {return value_;}
+    const T& value () const {return value_;}
+
+    T*       operator-> () {return &value_;}
+    const T* operator-> () const {return &value_;}
+
+    T&       operator* () {return value_;}
+    const T& operator* () const {return value_;}
+
+    explicit operator bool () const {return !null_;}
+
+  private:
+    T value_;
+    bool null_;
+  };
+}
+
+#endif // BUTL_OPTIONAL