+ typedef Vector<LabelScope, 8> LabelScopeStore;
+
+ class LabelScopePtr {
+ public:
+ LabelScopePtr()
+ : m_owner(0)
+ , m_index(0)
+ {
+ }
+ LabelScopePtr(LabelScopeStore& owner, size_t index)
+ : m_owner(&owner)
+ , m_index(index)
+ {
+ m_owner->at(index).ref();
+ }
+
+ LabelScopePtr(const LabelScopePtr& other)
+ : m_owner(other.m_owner)
+ , m_index(other.m_index)
+ {
+ if (m_owner)
+ m_owner->at(m_index).ref();
+ }
+
+ const LabelScopePtr& operator=(const LabelScopePtr& other)
+ {
+ if (other.m_owner)
+ other.m_owner->at(other.m_index).ref();
+ if (m_owner)
+ m_owner->at(m_index).deref();
+ m_owner = other.m_owner;
+ m_index = other.m_index;
+ return *this;
+ }
+
+ ~LabelScopePtr()
+ {
+ if (m_owner)
+ m_owner->at(m_index).deref();
+ }
+
+ bool operator!() const { return !m_owner; }
+
+ LabelScope& operator*() { ASSERT(m_owner); return m_owner->at(m_index); }
+ LabelScope* operator->() { ASSERT(m_owner); return &m_owner->at(m_index); }
+ const LabelScope& operator*() const { ASSERT(m_owner); return m_owner->at(m_index); }
+ const LabelScope* operator->() const { ASSERT(m_owner); return &m_owner->at(m_index); }
+
+ static LabelScopePtr null() { return LabelScopePtr(); }
+
+ private:
+ LabelScopeStore* m_owner;
+ size_t m_index;
+ };
+