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

Change-Id: I9636a41ad44b4218293833fd3e9456d9b07c731b

third_party/immer/example/vector/iota-slow.cpp

@@ -0,0 +1,25 @@
+//
+// 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:myiota/start
+immer::vector<int> myiota(immer::vector<int> v, int first, int last)
+{
+    for (auto i = first; i < last; ++i)
+        v = v.push_back(i);
+    return v;
+}
+// include:myiota/end
+
+int main()
+{
+    auto v = myiota({}, 0, 100);
+    std::copy(v.begin(), v.end(), std::ostream_iterator<int>{std::cout, "\n"});
+}