Problem: Examples are not compiled

Solution: Compile the examples when tests are compiled and using C++11
or greater.

Author: gummif

CMakeLists.txt

@@ -101,4 +101,7 @@ option(CPPZMQ_BUILD_TESTS "Whether or not to build the tests" ON)
 if (CPPZMQ_BUILD_TESTS)
     enable_testing()
     add_subdirectory(tests)
+    if (CMAKE_CXX_STANDARD AND NOT CMAKE_CXX_STANDARD EQUAL 98 AND CMAKE_CXX_STANDARD GREATER_EQUAL 11)
+        add_subdirectory(examples)
+    endif()
 endif()

examples/CMakeLists.txt

@@ -0,0 +1,23 @@
+cmake_minimum_required(VERSION 3.0 FATAL_ERROR)
+
+project(cppzmq-examples CXX)
+
+# place binaries and libraries according to GNU standards
+
+include(GNUInstallDirs)
+set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_LIBDIR})
+set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_LIBDIR})
+set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_BINDIR})
+
+find_package(Threads)
+
+add_executable(
+    pubsub_multithread_inproc
+    pubsub_multithread_inproc.cpp
+)
+
+target_link_libraries(
+    pubsub_multithread_inproc
+    PRIVATE cppzmq
+    PRIVATE ${CMAKE_THREAD_LIBS_INIT}
+)

examples/pubsub_multithread_inproc.cpp

@@ -40,9 +40,10 @@ void SubscriberThread1(zmq::context_t *ctx) {
         zmq::recv_result_t result =
           zmq::recv_multipart(subscriber, std::back_inserter(recv_msgs));
         assert(result && "recv failed");
+        assert(*result == 2);
 
-        std::cout << "Thread2: [" << recv_msgs[0].to_string_view() << "] "
-                  << recv_msgs[1].to_string_view() << std::endl;
+        std::cout << "Thread2: [" << recv_msgs[0].to_string() << "] "
+                  << recv_msgs[1].to_string() << std::endl;
     }
 }
 
@@ -60,9 +61,10 @@ void SubscriberThread2(zmq::context_t *ctx) {
         zmq::recv_result_t result =
           zmq::recv_multipart(subscriber, std::back_inserter(recv_msgs));
         assert(result && "recv failed");
+        assert(*result == 2);
 
-        std::cout << "Thread3: [" << recv_msgs[0].to_string_view() << "] "
-                  << recv_msgs[1].to_string_view() << std::endl;
+        std::cout << "Thread3: [" << recv_msgs[0].to_string() << "] "
+                  << recv_msgs[1].to_string() << std::endl;
     }
 }