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diff --git a/src/boost/libs/fiber/examples/adapt_method_calls.cpp b/src/boost/libs/fiber/examples/adapt_method_calls.cpp
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+++ b/src/boost/libs/fiber/examples/adapt_method_calls.cpp
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+//          Copyright Nat Goodspeed 2015.
+// 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/fiber/all.hpp>
+#include <memory>                   // std::shared_ptr
+#include <thread>
+#include <chrono>
+#include <iostream>
+#include <sstream>
+#include <exception>
+#include <cassert>
+
+/*****************************************************************************
+*   example async API
+*****************************************************************************/
+// introduce class-scope typedef
+struct AsyncAPIBase {
+    // error callback accepts an int error code; 0 == success
+    typedef int errorcode;
+};
+
+//[Response
+// every async operation receives a subclass instance of this abstract base
+// class through which to communicate its result
+struct Response {
+    typedef std::shared_ptr< Response > ptr;
+
+    // called if the operation succeeds
+    virtual void success( std::string const& data) = 0;
+
+    // called if the operation fails
+    virtual void error( AsyncAPIBase::errorcode ec) = 0;
+};
+//]
+
+// the actual async API
+class AsyncAPI: public AsyncAPIBase {
+public:
+    // constructor acquires some resource that can be read
+    AsyncAPI( std::string const& data);
+
+//[method_init_read
+    // derive Response subclass, instantiate, pass Response::ptr
+    void init_read( Response::ptr);
+//]
+
+    // ... other operations ...
+    void inject_error( errorcode ec);
+
+private:
+    std::string data_;
+    errorcode   injected_;
+};
+
+/*****************************************************************************
+*   fake AsyncAPI implementation... pay no attention to the little man behind
+*   the curtain...
+*****************************************************************************/
+AsyncAPI::AsyncAPI( std::string const& data) :
+    data_( data),
+    injected_( 0) {
+}
+
+void AsyncAPI::inject_error( errorcode ec) {
+    injected_ = ec;
+}
+
+void AsyncAPI::init_read( Response::ptr response) {
+    // make a local copy of injected_
+    errorcode injected( injected_);
+    // reset it synchronously with caller
+    injected_ = 0;
+    // local copy of data_ so we can capture in lambda
+    std::string data( data_);
+    // Simulate an asynchronous I/O operation by launching a detached thread
+    // that sleeps a bit before calling either completion method.
+    std::thread( [injected, response, data](){
+                     std::this_thread::sleep_for( std::chrono::milliseconds(100) );
+                     if ( ! injected) {
+                         // no error, call success()
+                         response->success( data);
+                     } else {
+                         // injected error, call error()
+                         response->error( injected);
+                     }            
+                 }).detach();
+}
+
+/*****************************************************************************
+*   adapters
+*****************************************************************************/
+// helper function
+std::runtime_error make_exception( std::string const& desc, AsyncAPI::errorcode);
+
+//[PromiseResponse
+class PromiseResponse: public Response {
+public:
+    // called if the operation succeeds
+    virtual void success( std::string const& data) {
+        promise_.set_value( data);
+    }
+
+    // called if the operation fails
+    virtual void error( AsyncAPIBase::errorcode ec) {
+        promise_.set_exception(
+                std::make_exception_ptr(
+                    make_exception("read", ec) ) );
+    }
+
+    boost::fibers::future< std::string > get_future() {
+        return promise_.get_future();
+    }
+
+private:
+    boost::fibers::promise< std::string >   promise_;
+};
+//]
+
+//[method_read
+std::string read( AsyncAPI & api) {
+    // Because init_read() requires a shared_ptr, we must allocate our
+    // ResponsePromise on the heap, even though we know its lifespan.
+    auto promisep( std::make_shared< PromiseResponse >() );
+    boost::fibers::future< std::string > future( promisep->get_future() );
+    // Both 'promisep' and 'future' will survive until our lambda has been
+    // called.
+    api.init_read( promisep);
+    return future.get();
+}
+//]
+
+/*****************************************************************************
+*   helpers
+*****************************************************************************/
+std::runtime_error make_exception( std::string const& desc, AsyncAPI::errorcode ec) {
+    std::ostringstream buffer;
+    buffer << "Error in AsyncAPI::" << desc << "(): " << ec;
+    return std::runtime_error( buffer.str() );
+}
+
+/*****************************************************************************
+*   driving logic
+*****************************************************************************/
+int main(int argc, char *argv[]) {
+    // prime AsyncAPI with some data
+    AsyncAPI api("abcd");
+
+    // successful read(): retrieve it
+    std::string data( read( api) );
+    assert(data == "abcd");
+
+    // read() with error
+    std::string thrown;
+    api.inject_error(1);
+    try {
+        data = read( api);
+    } catch ( std::exception const& e) {
+        thrown = e.what();
+    }
+    assert(thrown == make_exception("read", 1).what() );
+
+    std::cout << "done." << std::endl;
+
+    return EXIT_SUCCESS;
+}