88 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			88 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===----------------------------------------------------------------------===//
 | |
| //
 | |
| //                     The LLVM Compiler Infrastructure
 | |
| //
 | |
| // This file is dual licensed under the MIT and the University of Illinois Open
 | |
| // Source Licenses. See LICENSE.TXT for details.
 | |
| //
 | |
| //===----------------------------------------------------------------------===//
 | |
| 
 | |
| // <algorithm>
 | |
| 
 | |
| // template<class Iter, IntegralLike Size, Callable Generator>
 | |
| //   requires OutputIterator<Iter, Generator::result_type>
 | |
| //         && CopyConstructible<Generator>
 | |
| //   constexpr void      // constexpr after c++17
 | |
| //   generate_n(Iter first, Size n, Generator gen);
 | |
| 
 | |
| #ifdef _MSC_VER
 | |
| #pragma warning(disable: 4244) // conversion from 'const double' to 'int', possible loss of data
 | |
| #endif
 | |
| 
 | |
| #include <algorithm>
 | |
| #include <cassert>
 | |
| 
 | |
| #include "test_macros.h"
 | |
| #include "test_iterators.h"
 | |
| #include "user_defined_integral.hpp"
 | |
| 
 | |
| struct gen_test
 | |
| {
 | |
|     TEST_CONSTEXPR int operator()() const {return 2;}
 | |
| };
 | |
| 
 | |
| 
 | |
| #if TEST_STD_VER > 17
 | |
| TEST_CONSTEXPR bool test_constexpr() {
 | |
|     const size_t N = 5;
 | |
|     int ib[] = {0, 0, 0, 0, 0, 0}; // one bigger than N
 | |
| 
 | |
|     auto it = std::generate_n(std::begin(ib), N, gen_test());
 | |
| 
 | |
|     return it == (std::begin(ib) + N)
 | |
|         && std::all_of(std::begin(ib), it, [](int x) { return x == 2; })
 | |
|         && *it == 0 // don't overwrite the last value in the output array
 | |
|         ;
 | |
|     }
 | |
| #endif
 | |
| 
 | |
| 
 | |
| template <class Iter, class Size>
 | |
| void
 | |
| test2()
 | |
| {
 | |
|     const unsigned n = 4;
 | |
|     int ia[n] = {0};
 | |
|     assert(std::generate_n(Iter(ia), Size(n), gen_test()) == Iter(ia+n));
 | |
|     assert(ia[0] == 2);
 | |
|     assert(ia[1] == 2);
 | |
|     assert(ia[2] == 2);
 | |
|     assert(ia[3] == 2);
 | |
| }
 | |
| 
 | |
| template <class Iter>
 | |
| void
 | |
| test()
 | |
| {
 | |
|     test2<Iter, int>();
 | |
|     test2<Iter, unsigned int>();
 | |
|     test2<Iter, long>();
 | |
|     test2<Iter, unsigned long>();
 | |
|     test2<Iter, UserDefinedIntegral<unsigned> >();
 | |
|     test2<Iter, float>();
 | |
|     test2<Iter, double>();  // this is PR#35498
 | |
|     test2<Iter, long double>();
 | |
| }
 | |
| 
 | |
| int main()
 | |
| {
 | |
|     test<forward_iterator<int*> >();
 | |
|     test<bidirectional_iterator<int*> >();
 | |
|     test<random_access_iterator<int*> >();
 | |
|     test<int*>();
 | |
| 
 | |
| #if TEST_STD_VER > 17
 | |
|     static_assert(test_constexpr());
 | |
| #endif
 | |
| }
 |