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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14, c++17
// constexpr split_view(View base, Pattern pattern);
#include <algorithm>
#include <cassert>
#include <ranges>
#include <string_view>
#include <utility>
struct ViewWithCounting : std::ranges::view_base {
int* times_copied = nullptr;
int* times_moved = nullptr;
constexpr ViewWithCounting(int& copies_ctr, int& moves_ctr) : times_copied(&copies_ctr), times_moved(&moves_ctr) {}
constexpr ViewWithCounting(const ViewWithCounting& rhs)
: times_copied(rhs.times_copied), times_moved(rhs.times_moved) {
++(*times_copied);
}
constexpr ViewWithCounting(ViewWithCounting&& rhs) : times_copied(rhs.times_copied), times_moved(rhs.times_moved) {
++(*times_moved);
}
constexpr const char* begin() const { return nullptr; }
constexpr const char* end() const { return nullptr; }
constexpr ViewWithCounting& operator=(const ViewWithCounting&) = default;
constexpr ViewWithCounting& operator=(ViewWithCounting&&) = default;
constexpr bool operator==(const ViewWithCounting&) const { return true; }
};
constexpr bool test() {
{
std::string_view input = "abc def";
std::ranges::lazy_split_view<std::string_view, std::string_view> v(input, " ");
assert(v.base() == input);
assert(std::ranges::equal(*v.begin(), std::string_view{"abc"}));
}
// Make sure the arguments are moved, not copied.
{
using View = ViewWithCounting;
using Pattern = ViewWithCounting;
// Arguments are lvalues.
{
int view_copied = 0, view_moved = 0, pattern_copied = 0, pattern_moved = 0;
View view(view_copied, view_moved);
Pattern pattern(pattern_copied, pattern_moved);
std::ranges::split_view<View, Pattern> v(view, pattern);
assert(view_copied == 1); // The local variable is copied into the argument.
assert(view_moved == 1);
assert(pattern_copied == 1);
assert(pattern_moved == 1);
}
// Arguments are rvalues.
{
int view_copied = 0, view_moved = 0, pattern_copied = 0, pattern_moved = 0;
std::ranges::split_view<View, Pattern> v(View(view_copied, view_moved), Pattern(pattern_copied, pattern_moved));
assert(view_copied == 0);
assert(view_moved == 1);
assert(pattern_copied == 0);
assert(pattern_moved == 1);
}
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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