Adding test case for #774: using local dataflow without explicit name…

…space

tests/regressions/lcos/CMakeLists.txt

@@ -15,6 +15,11 @@ if(NOT MSVC10)
   set(tests ${tests}
       dataflow_future_swap
      )
+  if(HPX_HAVE_CXX11_LAMBDAS)
+    set(tests ${tests}
+        dataflow_using
+       )
+  endif()
 endif()
 
 set(async_callback_non_deduced_context_PARAMETERS THREADS_PER_LOCALITY 4)

tests/regressions/lcos/dataflow_future_swap.cpp

@@ -3,6 +3,9 @@
 //  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)
 
+// This test case demonstrates the issue described in #775: runtime error with 
+// local dataflow (copying futures?).
+
 #include <iostream>
 
 #include <hpx/hpx.hpp>

tests/regressions/lcos/dataflow_using.cpp

@@ -0,0 +1,48 @@
+//  Copyright (c) 2013 Mario Mulanski
+//
+//  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)
+
+// This test case demonstrates the issue described in #774: using local dataflow
+// without explicit namespace.
+
+#include <iostream>
+
+#include <hpx/hpx.hpp>
+#include <hpx/hpx_main.hpp>
+#include <hpx/lcos/local/dataflow.hpp>
+#include <hpx/util/unwrap.hpp>
+
+// the following line causes compile errors
+using hpx::lcos::local::dataflow;
+
+typedef hpx::lcos::future< double > future_type;
+
+template< typename Value >
+struct mul
+{
+    const Value a;
+
+    mul( const Value alpha )
+      : a( alpha )
+    {}
+
+    double operator() ( double x1 , double x2 ) const // this has to be const?!
+    {
+        return x1*x2*a;
+    }
+};
+
+int main()
+{
+    auto functor = hpx::util::unwrap(mul<double>( 0.5 ));
+    future_type f1 = hpx::make_ready_future( 1.0 );
+
+    // compile error even when using full namespace
+    future_type f2 = hpx::lcos::local::dataflow( functor , f1 , f1 );
+    future_type f3 = hpx::lcos::local::dataflow( hpx::util::unwrap(mul<double>( 2.0 )) , f1 , f1 );
+
+    hpx::wait_all(f1, f2, f3);
+
+    return 0;
+}