add capability for passing functions back to C++ from script land, plus an example usage.

chaiscript/CMakeLists.txt

@@ -15,6 +15,9 @@ if(Boost_FOUND)
    add_executable(chaiscript_test main.cpp)
    target_link_libraries(chaiscript_test ${Boost_LIBRARIES})
 
+   add_executable(chaiscript_callbacktest callbacktest.cpp)
+   target_link_libraries(chaiscript_callbacktest ${Boost_LIBRARIES})
+
 endif()
 
 

chaiscript/callbacktest.cpp

@@ -0,0 +1,57 @@
+#include <iostream>
+
+#include "chaiscript.hpp"
+#include "function_call.hpp"
+#include <boost/function.hpp>
+
+struct Callback_Handler
+{
+  typedef std::vector<std::pair<boost::function<std::string ()>,
+                        boost::function<double (int)> > > Callbacks;
+  
+  Callbacks m_callbacks;
+
+  void add_callbacks(boost::shared_ptr<dispatchkit::Proxy_Function> t_name,
+      boost::shared_ptr<dispatchkit::Proxy_Function> t_value)
+  {
+    m_callbacks.push_back(
+        std::make_pair(dispatchkit::build_function_caller<std::string>(t_name),
+                       dispatchkit::build_function_caller<double, int>(t_value)
+          )
+        );
+  }
+
+  void do_callbacks()
+  {
+    int i=1;
+    for (Callbacks::iterator itr = m_callbacks.begin();
+         itr != m_callbacks.end();
+         ++itr)
+    {
+      std::cout << "Name: " << itr->first() << "  =  " << itr->second(i) << std::endl;
+      ++i;
+    }
+  }
+};
+
+int main(int argc, char *argv[]) {
+
+    chaiscript::ChaiScript_Engine chai;
+
+    Callback_Handler cb_handler;
+    chai.get_eval_engine().add_object("cb_handler", boost::ref(cb_handler));
+    dispatchkit::register_function(chai.get_eval_engine(), &Callback_Handler::add_callbacks, "add_callbacks");
+
+    for (int i = 1; i < argc; ++i) {
+      try {
+        dispatchkit::Boxed_Value val = chai.evaluate_file(argv[i]);
+      }
+      catch (std::exception &e) {
+        std::cerr << "Could not open: " << argv[i] << std::endl;
+        exit(1);
+      }
+    }
+
+    cb_handler.do_callbacks();
+}
+

samples/callbacks.chai

@@ -0,0 +1,7 @@
+cb_handler.add_callbacks( function() { "First"; }, function (x) { x * 1.1; } );
+cb_handler.add_callbacks( function() { "TimesThree"; }, function (x) { x * 3.0001; } );
+cb_handler.add_callbacks( function() { "DivOnePtTwo"; }, function (x) { x / 1.2; } );
+
+
+
+