merge(3p/immer): Subtree merge at 'ad3e3556d' as 'third_party/immer'

Change-Id: I9636a41ad44b4218293833fd3e9456d9b07c731b

third_party/immer/example/vector/fizzbuzz.cpp

@@ -0,0 +1,34 @@
+//
+// 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/vector.hpp>
+
+#include <iostream>
+#include <string>
+
+// include:fizzbuzz/start
+immer::vector<std::string>
+fizzbuzz(immer::vector<std::string> v, int first, int last)
+{
+    for (auto i = first; i < last; ++i)
+        v = std::move(v).push_back(
+            i % 15 == 0 ? "FizzBuzz"
+                        : i % 5 == 0 ? "Bizz"
+                                     : i % 3 == 0 ? "Fizz" :
+                                                  /* else */ std::to_string(i));
+    return v;
+}
+// include:fizzbuzz/end
+
+int main()
+{
+    auto v = fizzbuzz({}, 0, 100);
+    std::copy(v.begin(),
+              v.end(),
+              std::ostream_iterator<std::string>{std::cout, "\n"});
+}