Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 101 insertions, 0 deletions

diff --git a/src/boost/libs/hana/example/tutorial/quickstart.cpp b/src/boost/libs/hana/example/tutorial/quickstart.cpp
new file mode 100644
index 000000000..6358e503b
--- /dev/null
+++ b/src/boost/libs/hana/example/tutorial/quickstart.cpp
@@ -0,0 +1,101 @@
+// Copyright Louis Dionne 2013-2017
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
+
+// Make sure `assert` always triggers an assertion
+#ifdef NDEBUG
+#   undef NDEBUG
+#endif
+
+//! [additional_setup]
+#include <cassert>
+#include <iostream>
+#include <string>
+
+struct Fish { std::string name; };
+struct Cat  { std::string name; };
+struct Dog  { std::string name; };
+//! [additional_setup]
+
+//! [includes]
+#include <boost/hana.hpp>
+namespace hana = boost::hana;
+//! [includes]
+
+
+int main() {
+
+//! [animals]
+auto animals = hana::make_tuple(Fish{"Nemo"}, Cat{"Garfield"}, Dog{"Snoopy"});
+//! [animals]
+
+//! [algorithms]
+using namespace hana::literals;
+
+// Access tuple elements with operator[] instead of std::get.
+Cat garfield = animals[1_c];
+
+// Perform high level algorithms on tuples (this is like std::transform)
+auto names = hana::transform(animals, [](auto a) {
+  return a.name;
+});
+
+assert(hana::reverse(names) == hana::make_tuple("Snoopy", "Garfield", "Nemo"));
+//! [algorithms]
+
+
+//! [type-level]
+auto animal_types = hana::make_tuple(hana::type_c<Fish*>, hana::type_c<Cat&>, hana::type_c<Dog>);
+
+auto no_pointers = hana::remove_if(animal_types, [](auto a) {
+  return hana::traits::is_pointer(a);
+});
+
+static_assert(no_pointers == hana::make_tuple(hana::type_c<Cat&>, hana::type_c<Dog>), "");
+//! [type-level]
+
+
+//! [has_name]
+auto has_name = hana::is_valid([](auto&& x) -> decltype((void)x.name) { });
+
+static_assert(has_name(garfield), "");
+static_assert(!has_name(1), "");
+//! [has_name]
+
+#if 0
+//! [screw_up]
+auto serialize = [](std::ostream& os, auto const& object) {
+  hana::for_each(os, [&](auto member) {
+    //           ^^ oopsie daisy!
+    os << member << std::endl;
+  });
+};
+//! [screw_up]
+#endif
+
+//! [serialization]
+// 1. Give introspection capabilities to 'Person'
+struct Person {
+  BOOST_HANA_DEFINE_STRUCT(Person,
+    (std::string, name),
+    (int, age)
+  );
+};
+
+// 2. Write a generic serializer (bear with std::ostream for the example)
+auto serialize = [](std::ostream& os, auto const& object) {
+  hana::for_each(hana::members(object), [&](auto member) {
+    os << member << std::endl;
+  });
+};
+
+// 3. Use it
+Person john{"John", 30};
+serialize(std::cout, john);
+
+// output:
+// John
+// 30
+//! [serialization]
+
+}