cxx2a-template-lambdas.cpp
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// RUN: %clang_cc1 -std=c++2a -emit-pch %s -o %t
// RUN: %clang_cc1 -std=c++2a -include-pch %t -verify %s
// expected-no-diagnostics
#ifndef HEADER
#define HEADER
auto l1 = []<int I>() constexpr -> int {
return I;
};
auto l2 = []<auto I>() constexpr -> decltype(I) {
return I;
};
auto l3 = []<class T>(auto i) constexpr -> T {
return T(i);
};
auto l4 = []<template<class> class T, class U>(T<U>, auto i) constexpr -> U {
return U(i);
};
#else /*included pch*/
static_assert(l1.operator()<5>() == 5);
static_assert(l1.operator()<6>() == 6);
static_assert(l2.operator()<7>() == 7);
static_assert(l2.operator()<nullptr>() == nullptr);
static_assert(l3.operator()<int>(8.4) == 8);
static_assert(l3.operator()<int>(9.9) == 9);
template<typename T>
struct DummyTemplate { };
static_assert(l4(DummyTemplate<float>(), 12) == 12.0);
static_assert(l4(DummyTemplate<int>(), 19.8) == 19);
#endif // HEADER