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-rw-r--r--clang/test/CXX/temp/temp.decls/temp.variadic/example-function.cpp86
1 files changed, 86 insertions, 0 deletions
diff --git a/clang/test/CXX/temp/temp.decls/temp.variadic/example-function.cpp b/clang/test/CXX/temp/temp.decls/temp.variadic/example-function.cpp
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index 0000000..e15203a
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+++ b/clang/test/CXX/temp/temp.decls/temp.variadic/example-function.cpp
@@ -0,0 +1,86 @@
+// RUN: %clang_cc1 -std=c++11 -fsyntax-only -verify %s
+
+// Example function implementation from the variadic templates proposal,
+// ISO C++ committee document number N2080.
+
+template<typename Signature> class function;
+
+template<typename R, typename... Args> class invoker_base {
+public:
+ virtual ~invoker_base() { }
+ virtual R invoke(Args...) = 0;
+ virtual invoker_base* clone() = 0;
+};
+
+template<typename F, typename R, typename... Args>
+class functor_invoker : public invoker_base<R, Args...> {
+public:
+ explicit functor_invoker(const F& f) : f(f) { }
+ R invoke(Args... args) { return f(args...); }
+ functor_invoker* clone() { return new functor_invoker(f); }
+
+private:
+ F f;
+};
+
+template<typename R, typename... Args>
+class function<R (Args...)> {
+public:
+ typedef R result_type;
+ function() : invoker (0) { }
+ function(const function& other) : invoker(0) {
+ if (other.invoker)
+ invoker = other.invoker->clone();
+ }
+
+ template<typename F> function(const F& f) : invoker(0) {
+ invoker = new functor_invoker<F, R, Args...>(f);
+ }
+
+ ~function() {
+ if (invoker)
+ delete invoker;
+ }
+
+ function& operator=(const function& other) {
+ function(other).swap(*this);
+ return *this;
+ }
+
+ template<typename F>
+ function& operator=(const F& f) {
+ function(f).swap(*this);
+ return *this;
+ }
+
+ void swap(function& other) {
+ invoker_base<R, Args...>* tmp = invoker;
+ invoker = other.invoker;
+ other.invoker = tmp;
+ }
+
+ result_type operator()(Args... args) const {
+ return invoker->invoke(args...);
+ }
+
+private:
+ invoker_base<R, Args...>* invoker;
+};
+
+template<typename T>
+struct add {
+ T operator()(T x, T y) { return x + y; }
+};
+
+int add_ints(int x, int y) { return x + y; }
+
+void test_function() {
+ function<int(int, int)> f2a;
+ function<int(int, int)> f2b = add<int>();
+ function<int(int, int)> f2c = add<float>();
+ function<int(int, int)> f2d(f2b);
+ function<int(int, int)> f2e = &add_ints;
+ f2c = f2d;
+ f2d = &add_ints;
+ f2c(1.0, 3);
+}