Author: marshall Date: Wed May 24 21:29:54 2017 New Revision: 303833 URL: http://llvm.org/viewvc/llvm-project?rev=303833&view=rev Log: Add non-parallel version of for_each_n (+tests) from the Parallelism TS
Added: libcxx/trunk/test/std/algorithms/alg.nonmodifying/alg.foreach/for_each_n.pass.cpp Modified: libcxx/trunk/include/algorithm Modified: libcxx/trunk/include/algorithm URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/algorithm?rev=303833&r1=303832&r2=303833&view=diff ============================================================================== --- libcxx/trunk/include/algorithm (original) +++ libcxx/trunk/include/algorithm Wed May 24 21:29:54 2017 @@ -35,6 +35,9 @@ template <class InputIterator, class Fun Function for_each(InputIterator first, InputIterator last, Function f); +template<class InputIterator, class Size, class Function> + InputIterator for_each_n(InputIterator first, Size n, Function f); // C++17 + template <class InputIterator, class T> InputIterator find(InputIterator first, InputIterator last, const T& value); @@ -961,6 +964,24 @@ for_each(_InputIterator __first, _InputI return __f; } +// for_each_n + +template <class _InputIterator, class _Size, class _Function> +inline _LIBCPP_INLINE_VISIBILITY +_InputIterator +for_each_n(_InputIterator __first, _Size __orig_n, _Function __f) +{ + typedef decltype(__convert_to_integral(__orig_n)) _IntegralSize; + _IntegralSize __n = __orig_n; + while (__n > 0) + { + __f(*__first); + ++__first; + --__n; + } + return __first; +} + // find template <class _InputIterator, class _Tp> Added: libcxx/trunk/test/std/algorithms/alg.nonmodifying/alg.foreach/for_each_n.pass.cpp URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/std/algorithms/alg.nonmodifying/alg.foreach/for_each_n.pass.cpp?rev=303833&view=auto ============================================================================== --- libcxx/trunk/test/std/algorithms/alg.nonmodifying/alg.foreach/for_each_n.pass.cpp (added) +++ libcxx/trunk/test/std/algorithms/alg.nonmodifying/alg.foreach/for_each_n.pass.cpp Wed May 24 21:29:54 2017 @@ -0,0 +1,61 @@ +//===----------------------------------------------------------------------===// +// +// 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> +// UNSUPPORTED: c++98, c++03, c++11, c++14 + +// template<class InputIterator, class Size, class Function> +// InputIterator for_each_n(InputIterator first, Size n, Function f); + + +#include <algorithm> +#include <cassert> + +#include "test_iterators.h" + +struct for_each_test +{ + for_each_test(int c) : count(c) {} + int count; + void operator()(int& i) {++i; ++count;} +}; + +int main() +{ + typedef input_iterator<int*> Iter; + int ia[] = {0, 1, 2, 3, 4, 5}; + const unsigned s = sizeof(ia)/sizeof(ia[0]); + + { + auto f = for_each_test(0); + Iter it = std::for_each_n(Iter(ia), 0, std::ref(f)); + assert(it == Iter(ia)); + assert(f.count == 0); + } + + { + auto f = for_each_test(0); + Iter it = std::for_each_n(Iter(ia), s, std::ref(f)); + + assert(it == Iter(ia+s)); + assert(f.count == s); + for (unsigned i = 0; i < s; ++i) + assert(ia[i] == static_cast<int>(i+1)); + } + + { + auto f = for_each_test(0); + Iter it = std::for_each_n(Iter(ia), 1, std::ref(f)); + + assert(it == Iter(ia+1)); + assert(f.count == 1); + for (unsigned i = 0; i < 1; ++i) + assert(ia[i] == static_cast<int>(i+2)); + } +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits