// { dg-options "-std=gnu++0x" }
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// { dg-options "-std=gnu++0x" }
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// { dg-do "run" }
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// { dg-do "run" }
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// An implementation of TR1's using variadic teplates
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// An implementation of TR1's using variadic teplates
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// Contributed by Douglas Gregor
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// Contributed by Douglas Gregor
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#include
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#include
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#include
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#include
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#include
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#include
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// Trivial reference_wrapper
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// Trivial reference_wrapper
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template
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template
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struct reference_wrapper
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struct reference_wrapper
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{
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{
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reference_wrapper(T& x) : ptr(&x) { }
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reference_wrapper(T& x) : ptr(&x) { }
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operator T&() const { return *ptr; }
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operator T&() const { return *ptr; }
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T* ptr;
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T* ptr;
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};
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};
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template reference_wrapper ref(T& x) { return x; }
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template reference_wrapper ref(T& x) { return x; }
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template reference_wrapper cref(const T& x) { return x; }
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template reference_wrapper cref(const T& x) { return x; }
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// Simple type-traits we'll need
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// Simple type-traits we'll need
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template
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template
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struct add_reference
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struct add_reference
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{
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{
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typedef T& type;
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typedef T& type;
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};
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};
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template
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template
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struct add_reference
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struct add_reference
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{
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{
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typedef T& type;
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typedef T& type;
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};
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};
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template
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template
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struct is_same
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struct is_same
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{
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{
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static const bool value = false;
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static const bool value = false;
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};
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};
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template
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template
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struct is_same
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struct is_same
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{
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{
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static const bool value = true;
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static const bool value = true;
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};
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};
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// For creating the constructor parameters of tuple<>
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// For creating the constructor parameters of tuple<>
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template
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template
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struct add_const_reference
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struct add_const_reference
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{
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{
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typedef const T& type;
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typedef const T& type;
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};
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};
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template
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template
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struct add_const_reference
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struct add_const_reference
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{
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{
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typedef T& type;
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typedef T& type;
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};
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};
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// 6.1.3 Class template tuple
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// 6.1.3 Class template tuple
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template
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template
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class tuple;
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class tuple;
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template<> class tuple<> { };
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template<> class tuple<> { };
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template
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template
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class tuple
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class tuple
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: private tuple
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: private tuple
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{
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{
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typedef tuple inherited;
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typedef tuple inherited;
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public:
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public:
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tuple() { }
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tuple() { }
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// implicit copy-constructor is okay
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// implicit copy-constructor is okay
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tuple(typename add_const_reference::type v,
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tuple(typename add_const_reference::type v,
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typename add_const_reference::type... vtail)
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typename add_const_reference::type... vtail)
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: m_head(v), inherited(vtail...) { }
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: m_head(v), inherited(vtail...) { }
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template
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template
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tuple(const tuple& other)
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tuple(const tuple& other)
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: m_head(other.head()), inherited(other.tail()) { }
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: m_head(other.head()), inherited(other.tail()) { }
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template
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template
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tuple& operator=(const tuple& other)
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tuple& operator=(const tuple& other)
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{
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{
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m_head = other.head();
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m_head = other.head();
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tail() = other.tail();
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tail() = other.tail();
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return *this;
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return *this;
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}
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}
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typename add_reference::type head() { return m_head; }
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typename add_reference::type head() { return m_head; }
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typename add_reference::type head() const { return m_head; }
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typename add_reference::type head() const { return m_head; }
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inherited& tail() { return *this; }
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inherited& tail() { return *this; }
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const inherited& tail() const { return *this; }
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const inherited& tail() const { return *this; }
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protected:
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protected:
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Head m_head;
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Head m_head;
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};
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};
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template
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template
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struct make_tuple_result
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struct make_tuple_result
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{
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{
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typedef T type;
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typedef T type;
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};
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};
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template
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template
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struct make_tuple_result >
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struct make_tuple_result >
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{
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{
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typedef T& type;
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typedef T& type;
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};
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};
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// 6.1.3.2 Tuple creation functions
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// 6.1.3.2 Tuple creation functions
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struct ignore_t {
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struct ignore_t {
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template ignore_t& operator=(const T&) { return *this; }
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template ignore_t& operator=(const T&) { return *this; }
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} ignore;
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} ignore;
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template
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template
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tuple::type...>
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tuple::type...>
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make_tuple(const Values&... values)
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make_tuple(const Values&... values)
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{
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{
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return tuple::type...>(values...);
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return tuple::type...>(values...);
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}
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}
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template
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template
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tuple tie(Values&... values)
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tuple tie(Values&... values)
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{
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{
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return tuple(values...);
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return tuple(values...);
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}
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}
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// 6.1.3.3 Tuple helper classes
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// 6.1.3.3 Tuple helper classes
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template
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template
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struct tuple_size;
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struct tuple_size;
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template<>
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template<>
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struct tuple_size >
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struct tuple_size >
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{
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{
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static const std::size_t value = 0;
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static const std::size_t value = 0;
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};
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};
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template
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template
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struct tuple_size >
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struct tuple_size >
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{
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{
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static const std::size_t value = 1 + tuple_size >::value;
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static const std::size_t value = 1 + tuple_size >::value;
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};
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};
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template
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template
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struct tuple_element;
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struct tuple_element;
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template
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template
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struct tuple_element >
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struct tuple_element >
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{
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{
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typedef typename tuple_element >::type type;
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typedef typename tuple_element >::type type;
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};
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};
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template
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template
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struct tuple_element<0, tuple >
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struct tuple_element<0, tuple >
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{
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{
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typedef Head type;
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typedef Head type;
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};
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};
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// 6.1.3.4 Element access
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// 6.1.3.4 Element access
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template
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template
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class get_impl;
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class get_impl;
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template
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template
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class get_impl >
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class get_impl >
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{
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{
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typedef typename tuple_element >::type Element;
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typedef typename tuple_element >::type Element;
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typedef typename add_reference::type RJ;
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typedef typename add_reference::type RJ;
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typedef typename add_const_reference::type PJ;
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typedef typename add_const_reference::type PJ;
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typedef get_impl > Next;
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typedef get_impl > Next;
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public:
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public:
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static RJ get(tuple& t)
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static RJ get(tuple& t)
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{ return Next::get(t.tail()); }
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{ return Next::get(t.tail()); }
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static PJ get(const tuple& t)
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static PJ get(const tuple& t)
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{ return Next::get(t.tail()); }
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{ return Next::get(t.tail()); }
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};
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};
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template
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template
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class get_impl<0, tuple >
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class get_impl<0, tuple >
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{
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{
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typedef typename add_reference::type RJ;
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typedef typename add_reference::type RJ;
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typedef typename add_const_reference::type PJ;
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typedef typename add_const_reference::type PJ;
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public:
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public:
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static RJ get(tuple& t) { return t.head(); }
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static RJ get(tuple& t) { return t.head(); }
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static PJ get(const tuple& t) { return t.head(); }
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static PJ get(const tuple& t) { return t.head(); }
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};
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};
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template
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template
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typename add_reference<
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typename add_reference<
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typename tuple_element >::type
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typename tuple_element >::type
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>::type
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>::type
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get(tuple& t)
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get(tuple& t)
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{
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{
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return get_impl >::get(t);
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return get_impl >::get(t);
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}
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}
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template
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template
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typename add_const_reference<
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typename add_const_reference<
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typename tuple_element >::type
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typename tuple_element >::type
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>::type
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>::type
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get(const tuple& t)
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get(const tuple& t)
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{
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{
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return get_impl >::get(t);
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return get_impl >::get(t);
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}
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}
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// 6.1.3.5 Relational operators
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// 6.1.3.5 Relational operators
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inline bool operator==(const tuple<>&, const tuple<>&) { return true; }
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inline bool operator==(const tuple<>&, const tuple<>&) { return true; }
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template
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template
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bool operator==(const tuple& t, const tuple& u)
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bool operator==(const tuple& t, const tuple& u)
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{
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{
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return t.head() == u.head() && t.tail() == u.tail();
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return t.head() == u.head() && t.tail() == u.tail();
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}
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}
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template
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template
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bool operator!=(const tuple& t, const tuple& u)
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bool operator!=(const tuple& t, const tuple& u)
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{
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{
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return !(t == u);
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return !(t == u);
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}
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}
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inline bool operator<(const tuple<>&, const tuple<>&) { return false; }
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inline bool operator<(const tuple<>&, const tuple<>&) { return false; }
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template
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template
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bool operator<(const tuple& t, const tuple& u)
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bool operator<(const tuple& t, const tuple& u)
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{
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{
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return (t.head() < u.head() ||
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return (t.head() < u.head() ||
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(!(t.head() < u.head()) && t.tail() < u.tail()));
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(!(t.head() < u.head()) && t.tail() < u.tail()));
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}
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}
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template
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template
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bool operator>(const tuple& t, const tuple& u)
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bool operator>(const tuple& t, const tuple& u)
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{
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{
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return u < t;
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return u < t;
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}
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}
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template
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template
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bool operator<=(const tuple& t, const tuple& u)
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bool operator<=(const tuple& t, const tuple& u)
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{
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{
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return !(u < t);
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return !(u < t);
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}
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}
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template
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template
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bool operator>=(const tuple& t, const tuple& u)
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bool operator>=(const tuple& t, const tuple& u)
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{
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{
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return !(t < u);
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return !(t < u);
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}
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}
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int a0[tuple_size >::value == 0? 1 : -1];
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int a0[tuple_size >::value == 0? 1 : -1];
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int a1[tuple_size >::value == 3? 1 : -1];
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int a1[tuple_size >::value == 3? 1 : -1];
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int a2a[is_same >::type, int>
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int a2a[is_same >::type, int>
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::value? 1 : -1];
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::value? 1 : -1];
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int a2b[is_same >::type, float>
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int a2b[is_same >::type, float>
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::value? 1 : -1];
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::value? 1 : -1];
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int a2c[is_same >::type, double>
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int a2c[is_same >::type, double>
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::value? 1 : -1];
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::value? 1 : -1];
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int main()
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int main()
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{
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{
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tuple<> t0;
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tuple<> t0;
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tuple t1(1);
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tuple t1(1);
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tuple t2(1, 3.14159f);
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tuple t2(1, 3.14159f);
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tuple t3a(1, 3.14159f, "Hello, world!");
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tuple t3a(1, 3.14159f, "Hello, world!");
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tuple t3b(t3a);
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tuple t3b(t3a);
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t3b = t3a;
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t3b = t3a;
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// t3a = t3b; DPG: triggers an error, as it should.
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// t3a = t3b; DPG: triggers an error, as it should.
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tuple t3c =
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tuple t3c =
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make_tuple(17, 2.718281828, std::string("Fun"));
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make_tuple(17, 2.718281828, std::string("Fun"));
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int seventeen = 17;
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int seventeen = 17;
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double pi = 3.14159;
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double pi = 3.14159;
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tuple seventeen_pi = make_tuple(ref(seventeen), ref(pi));
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tuple seventeen_pi = make_tuple(ref(seventeen), ref(pi));
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tuple seventeen_pi2 =
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tuple seventeen_pi2 =
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make_tuple(ref(seventeen), cref(pi));
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make_tuple(ref(seventeen), cref(pi));
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tuple seventeen_pi_tied = tie(seventeen, pi);
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tuple seventeen_pi_tied = tie(seventeen, pi);
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assert(get<0>(t3a) == 1);
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assert(get<0>(t3a) == 1);
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assert(get<1>(t3a) == 3.14159f);
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assert(get<1>(t3a) == 3.14159f);
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assert(std::strcmp(get<2>(t3a), "Hello, world!") == 0);
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assert(std::strcmp(get<2>(t3a), "Hello, world!") == 0);
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assert(t3a == t3b);
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assert(t3a == t3b);
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assert(!(t3a != t3b));
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assert(!(t3a != t3b));
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assert(!(t3a < t3b));
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assert(!(t3a < t3b));
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assert(!(t3a > t3b));
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assert(!(t3a > t3b));
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assert(t3a <= t3b && t3b <= t3a);
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assert(t3a <= t3b && t3b <= t3a);
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assert(t3a >= t3b && t3b >= t3a);
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assert(t3a >= t3b && t3b >= t3a);
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}
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}
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