[libcxx-commits] [libcxx] [libc++] implement std::flat_set (PR #125241)

[Louis Dionne via libcxx-commits]

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@@ -0,0 +1,42 @@
+//
+// 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, c++20
+
+// <flat_set>
+
+// test that iterators from different types of flat_set are not compatible
+
+#include <deque>
+#include <functional>
+#include <flat_set>
+#include <type_traits>
+
+using Iter1 = std::flat_set<int>::iterator;
+using Iter2 = std::flat_set<double>::iterator;
+using Iter3 = std::flat_set<int, std::greater<>>::iterator;
+using Iter4 = std::flat_set<int, std::less<int>, std::deque<int>>::iterator;
+
+static_assert(std::is_convertible_v<Iter1, Iter1>);
+static_assert(!std::is_convertible_v<Iter1, Iter2>);
+static_assert(!std::is_convertible_v<Iter1, Iter3>);
+static_assert(!std::is_convertible_v<Iter1, Iter4>);
+
+static_assert(!std::is_convertible_v<Iter2, Iter1>);
+static_assert(std::is_convertible_v<Iter2, Iter2>);
+static_assert(!std::is_convertible_v<Iter2, Iter3>);
+static_assert(!std::is_convertible_v<Iter2, Iter4>);
+
+static_assert(!std::is_convertible_v<Iter3, Iter1>);
+static_assert(!std::is_convertible_v<Iter3, Iter2>);
+static_assert(std::is_convertible_v<Iter3, Iter3>);
+static_assert(!std::is_convertible_v<Iter3, Iter4>);
+
+static_assert(!std::is_convertible_v<Iter4, Iter1>);
+static_assert(!std::is_convertible_v<Iter4, Iter2>);
+static_assert(!std::is_convertible_v<Iter4, Iter3>);
+static_assert(std::is_convertible_v<Iter4, Iter4>);
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ldionne wrote:

Nit: newline

https://github.com/llvm/llvm-project/pull/125241