Fixed libunwind backend, added docs, fixed tests and compilation, changed return type of stacktrace::operator[]

example/getting_started.cpp

@@ -0,0 +1,58 @@
+// Copyright Antony Polukhin, 2016.
+//
+// Distributed under the Boost Software License, Version 1.0. (See
+// accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+#include <boost/function.hpp>
+struct events {
+    typedef boost::function<void (float)> callback_type;
+
+    static void from_keyboard(callback_type callback);
+    static void from_network(callback_type callback);
+};
+
+
+#include <boost/stacktrace.hpp>
+#include <iostream>
+BOOST_NOINLINE void validate_positive(float f) {
+    if (f < 0.f) {
+        std::cerr << "Negative number " << f << " detected. Call stack:\n"
+            << boost::stacktrace::stacktrace() << '\n';
+    }
+}
+
+
+
+
+boost::function<void (float)> on_keyboard;
+boost::function<void (float)> on_network;
+
+BOOST_NOINLINE void keyboard_event() {
+    on_keyboard(-0.1f);
+}
+
+BOOST_NOINLINE void network_event() {
+    on_network(1.0f);
+}
+
+void events::from_keyboard(events::callback_type callback) {
+    on_keyboard = callback;
+}
+
+void events::from_network(events::callback_type callback) {
+    on_network = callback;
+}
+
+
+
+int main() {
+    events::from_keyboard(&validate_positive);
+    events::from_network(&validate_positive);
+
+    keyboard_event();
+    network_event();
+}
+
+
+