Squashed 'third_party/immer/' content from commit ad3e3556d

git-subtree-dir: third_party/immer
git-subtree-split: ad3e3556d38bb75966dd24c61a774970a7c7957e

example/array/array.cpp

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+//
+// immer: immutable data structures for C++
+// Copyright (C) 2016, 2017, 2018 Juan Pedro Bolivar Puente
+//
+// This software is distributed under the Boost Software License, Version 1.0.
+// See accompanying file LICENSE or copy at http://boost.org/LICENSE_1_0.txt
+//
+
+#include <immer/array.hpp>
+
+#include <cassert>
+
+int main()
+{
+    {
+        // include:push-back/start
+        auto v1 = immer::array<int>{1};
+        auto v2 = v1.push_back(8);
+
+        assert((v1 == immer::array<int>{1}));
+        assert((v2 == immer::array<int>{1, 8}));
+        // include:push-back/end
+    }
+
+    {
+        // include:set/start
+        auto v1 = immer::array<int>{1, 2, 3};
+        auto v2 = v1.set(0, 5);
+
+        assert((v1 == immer::array<int>{1, 2, 3}));
+        assert((v2 == immer::array<int>{5, 2, 3}));
+        // include:set/end
+    }
+
+    {
+        // include:update/start
+        auto v1 = immer::array<int>{1, 2, 3, 4};
+        auto v2 = v1.update(2, [&](auto l) { return ++l; });
+
+        assert((v1 == immer::array<int>{1, 2, 3, 4}));
+        assert((v2 == immer::array<int>{1, 2, 4, 4}));
+        // include:update/end
+    }
+
+    {
+        // include:take/start
+        auto v1 = immer::array<int>{1, 2, 3, 4, 5, 6};
+        auto v2 = v1.take(3);
+
+        assert((v1 == immer::array<int>{1, 2, 3, 4, 5, 6}));
+        assert((v2 == immer::array<int>{1, 2, 3}));
+        // include:take/end
+    }
+}