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-rw-r--r--clang/test/CXX/temp/temp.decls/temp.variadic/metafunctions.cpp274
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diff --git a/clang/test/CXX/temp/temp.decls/temp.variadic/metafunctions.cpp b/clang/test/CXX/temp/temp.decls/temp.variadic/metafunctions.cpp
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index 0000000..73cbd07
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+++ b/clang/test/CXX/temp/temp.decls/temp.variadic/metafunctions.cpp
@@ -0,0 +1,274 @@
+// RUN: %clang_cc1 -std=c++11 -fsyntax-only -verify %s
+
+// This is a collection of various template metafunctions involving
+// variadic templates, which are meant to exercise common use cases.
+template<typename T, typename U>
+struct is_same {
+ static const bool value = false;
+};
+
+template<typename T>
+struct is_same<T, T> {
+ static const bool value = true;
+};
+
+template<typename...> struct tuple { };
+template<int ...> struct int_tuple { };
+template<typename T, typename U> struct pair { };
+
+namespace Count {
+ template<typename Head, typename ...Tail>
+ struct count {
+ static const unsigned value = 1 + count<Tail...>::value;
+ };
+
+ template<typename T>
+ struct count<T> {
+ static const unsigned value = 1;
+ };
+
+ int check1[count<int>::value == 1? 1 : -1];
+ int check2[count<float, double>::value == 2? 1 : -1];
+ int check3[count<char, signed char, unsigned char>::value == 3? 1 : -1];
+}
+
+namespace CountWithPackExpansion {
+ template<typename ...> struct count;
+
+ template<typename Head, typename ...Tail>
+ struct count<Head, Tail...> {
+ static const unsigned value = 1 + count<Tail...>::value;
+ };
+
+ template<>
+ struct count<> {
+ static const unsigned value = 0;
+ };
+
+ int check0[count<>::value == 0? 1 : -1];
+ int check1[count<int>::value == 1? 1 : -1];
+ int check2[count<float, double>::value == 2? 1 : -1];
+ int check3[count<char, signed char, unsigned char>::value == 3? 1 : -1];
+}
+
+namespace Replace {
+ // Simple metafunction that replaces the template arguments of
+ // template template parameters with 'int'.
+ template<typename T>
+ struct EverythingToInt;
+
+ template<template<typename ...> class TT, typename T1, typename T2>
+ struct EverythingToInt<TT<T1, T2> > {
+ typedef TT<int, int> type;
+ };
+
+ int check0[is_same<EverythingToInt<tuple<double, float>>::type,
+ tuple<int, int>>::value? 1 : -1];
+}
+
+namespace Math {
+ template<int ...Values>
+ struct double_values {
+ typedef int_tuple<Values*2 ...> type;
+ };
+
+ int check0[is_same<double_values<1, 2, -3>::type,
+ int_tuple<2, 4, -6>>::value? 1 : -1];
+
+ template<int ...Values>
+ struct square {
+ typedef int_tuple<(Values*Values)...> type;
+ };
+
+ int check1[is_same<square<1, 2, -3>::type,
+ int_tuple<1, 4, 9>>::value? 1 : -1];
+
+ template<typename IntTuple> struct square_tuple;
+
+ template<int ...Values>
+ struct square_tuple<int_tuple<Values...>> {
+ typedef int_tuple<(Values*Values)...> type;
+ };
+
+ int check2[is_same<square_tuple<int_tuple<1, 2, -3> >::type,
+ int_tuple<1, 4, 9>>::value? 1 : -1];
+
+ template<int ...Values> struct sum;
+
+ template<int First, int ...Rest>
+ struct sum<First, Rest...> {
+ static const int value = First + sum<Rest...>::value;
+ };
+
+ template<>
+ struct sum<> {
+ static const int value = 0;
+ };
+
+ int check3[sum<1, 2, 3, 4, 5>::value == 15? 1 : -1];
+
+ template<int ... Values>
+ struct lazy_sum {
+ int operator()() {
+ return sum<Values...>::value;
+ }
+ };
+
+ void f() {
+ lazy_sum<1, 2, 3, 4, 5>()();
+ }
+}
+
+namespace ListMath {
+ template<typename T, T ... V> struct add;
+
+ template<typename T, T i, T ... V>
+ struct add<T, i, V...> {
+ static const T value = i + add<T, V...>::value;
+ };
+
+ template<typename T>
+ struct add<T> {
+ static const T value = T();
+ };
+
+ template<typename T, T ... V>
+ struct List {
+ struct sum {
+ static const T value = add<T, V...>::value;
+ };
+ };
+
+ template<int ... V>
+ struct ListI : public List<int, V...> {
+ };
+
+ int check0[ListI<1, 2, 3>::sum::value == 6? 1 : -1];
+}
+
+namespace Indices {
+ template<unsigned I, unsigned N, typename IntTuple>
+ struct build_indices_impl;
+
+ template<unsigned I, unsigned N, int ...Indices>
+ struct build_indices_impl<I, N, int_tuple<Indices...> >
+ : build_indices_impl<I+1, N, int_tuple<Indices..., I> > {
+ };
+
+ template<unsigned N, int ...Indices>
+ struct build_indices_impl<N, N, int_tuple<Indices...> > {
+ typedef int_tuple<Indices...> type;
+ };
+
+ template<unsigned N>
+ struct build_indices : build_indices_impl<0, N, int_tuple<> > { };
+
+ int check0[is_same<build_indices<5>::type,
+ int_tuple<0, 1, 2, 3, 4>>::value? 1 : -1];
+}
+
+namespace TemplateTemplateApply {
+ template<typename T, template<class> class ...Meta>
+ struct apply_each {
+ typedef tuple<typename Meta<T>::type...> type;
+ };
+
+ template<typename T>
+ struct add_reference {
+ typedef T& type;
+ };
+
+ template<typename T>
+ struct add_pointer {
+ typedef T* type;
+ };
+
+ template<typename T>
+ struct add_const {
+ typedef const T type;
+ };
+
+ int check0[is_same<apply_each<int,
+ add_reference, add_pointer, add_const>::type,
+ tuple<int&, int*, int const>>::value? 1 : -1];
+
+ template<typename T, template<class> class ...Meta>
+ struct apply_each_indirect {
+ typedef typename apply_each<T, Meta...>::type type;
+ };
+
+ int check1[is_same<apply_each_indirect<int, add_reference, add_pointer,
+ add_const>::type,
+ tuple<int&, int*, int const>>::value? 1 : -1];
+
+ template<typename T, typename ...Meta>
+ struct apply_each_nested {
+ typedef typename apply_each<T, Meta::template apply...>::type type;
+ };
+
+ struct add_reference_meta {
+ template<typename T>
+ struct apply {
+ typedef T& type;
+ };
+ };
+
+ struct add_pointer_meta {
+ template<typename T>
+ struct apply {
+ typedef T* type;
+ };
+ };
+
+ struct add_const_meta {
+ template<typename T>
+ struct apply {
+ typedef const T type;
+ };
+ };
+
+ int check2[is_same<apply_each_nested<int, add_reference_meta,
+ add_pointer_meta, add_const_meta>::type,
+ tuple<int&, int*, int const>>::value? 1 : -1];
+
+}
+
+namespace FunctionTypes {
+ template<typename FunctionType>
+ struct Arity;
+
+ template<typename R, typename ...Types>
+ struct Arity<R(Types...)> {
+ static const unsigned value = sizeof...(Types);
+ };
+
+ template<typename R, typename ...Types>
+ struct Arity<R(Types......)> {
+ static const unsigned value = sizeof...(Types);
+ };
+
+ template<typename R, typename T1, typename T2, typename T3, typename T4>
+ struct Arity<R(T1, T2, T3, T4)>; // expected-note{{template is declared here}}
+
+ int check0[Arity<int()>::value == 0? 1 : -1];
+ int check1[Arity<int(float, double)>::value == 2? 1 : -1];
+ int check2[Arity<int(float...)>::value == 1? 1 : -1];
+ int check3[Arity<int(float, double, long double...)>::value == 3? 1 : -1];
+ Arity<int(float, double, long double, char)> check4; // expected-error{{implicit instantiation of undefined template 'FunctionTypes::Arity<int (float, double, long double, char)>'}}
+}
+
+namespace SuperReplace {
+ template<typename T>
+ struct replace_with_int {
+ typedef int type;
+ };
+
+ template<template<typename ...> class TT, typename ...Types>
+ struct replace_with_int<TT<Types...>> {
+ typedef TT<typename replace_with_int<Types>::type...> type;
+ };
+
+ int check0[is_same<replace_with_int<pair<tuple<float, double, short>,
+ pair<char, unsigned char>>>::type,
+ pair<tuple<int, int, int>, pair<int, int>>>::value? 1 : -1];
+}