_Mem: Make eject return the executed command or NULL. Use it in injec…

…t_productions. See issue #123.

AERA/test_mem.cpp

@@ -154,7 +154,7 @@ TestMem<O, S>::findObject(std::vector<Code*> *objects, const char* name) {
   return NULL;
 }
 
-template<class O, class S> void TestMem<O, S>::eject(Code *command) {
+template<class O, class S> Code* TestMem<O, S>::eject(Code *command) {
   uint16 function = (command->code(CMD_FUNCTION).atom_ >> 8) & 0x000000FF;
 
   if (function == ready_opcode_) {
@@ -167,43 +167,44 @@ template<class O, class S> void TestMem<O, S>::eject(Code *command) {
         if (!(command->code_size() >= 3 && command->code(args_set_index + 2).getDescriptor() == Atom::R_PTR &&
               command->references_size() > command->code(args_set_index + 2).asIndex())) {
           cout << "WARNING: Cannot get the object for ready \"ball\"" << endl;
-          return;
+          return NULL;
         }
         if (!velocity_y_property_) {
           cout << "WARNING: Can't find the velocity_y property" << endl;
-          return;
+          return NULL;
         }
         if (!position_y_property_) {
           cout << "WARNING: Can't find the position_y property" << endl;
-          return;
+          return NULL;
         }
 
         Code* obj = command->get_reference(command->code(args_set_index + 2).asIndex());
         if (!position_y_obj_) {
           // This is the first call. Remember the object whose position we're reporting.
           position_y_obj_ = obj;
           startTimeTickThread();
+          return command;
         }
         else {
           if (position_y_obj_ != obj)
             // For now, don't allow tracking multiple objects.
-            return;
+            return NULL;
         }
       }
       else {
         cout << "WARNING: Ignoring unrecognized ready command identifier: " << identifier << endl;
-        return;
+        return NULL;
       }
     }
   }
   else if (function == set_velocity_y_opcode_) {
     if (!velocity_y_property_) {
       cout << "WARNING: Can't find the velocity_y property" << endl;
-      return;
+      return NULL;
     }
     if (!position_y_property_) {
       cout << "WARNING: Can't find the position_y property" << endl;
-      return;
+      return NULL;
     }
 
     auto now = r_exec::Now();
@@ -220,22 +221,23 @@ template<class O, class S> void TestMem<O, S>::eject(Code *command) {
     else {
       if (position_y_obj_ != obj)
         // For now, don't allow tracking the velocity of multiple objects.
-        return;
+        return NULL;
     }
 
     velocity_y_ = command->code(args_set_index + 2).asFloat();
     // Let onTimeTick inject the new velocity_y.
+    return command;
   }
   else if (function == move_y_plus_opcode_ ||
     function == move_y_minus_opcode_) {
     if (!position_property_) {
       cout << "WARNING: Can't find the position property" << endl;
-      return;
+      return NULL;
     }
     for (int i = 0; i <= 9; ++i) {
       if (!yEnt_[i]) {
         cout << "WARNING: Can't find the entities y0, y1, etc." << endl;
-        return;
+        return NULL;
       }
     }
 
@@ -249,17 +251,16 @@ template<class O, class S> void TestMem<O, S>::eject(Code *command) {
       discretePositionObj_ = obj;
       discretePosition_ = yEnt_[0];
       startTimeTickThread();
-      return;
     }
     else {
       if (discretePositionObj_ != obj)
         // For now, don't allow tracking multiple objects.
-        return;
+        return NULL;
     }
 
     if (nextDiscretePosition_)
       // A previous move command is still pending execution.
-      return;
+      return NULL;
 
     // nextDiscretePosition_ will become the position at the next sampling period.
     lastCommandTime_ = now;
@@ -277,7 +278,10 @@ template<class O, class S> void TestMem<O, S>::eject(Code *command) {
       }
     }
     // Let onTimeTick inject the new position.
+    return command;
   }
+
+  return NULL;
 }
 
 template<class O, class S> void TestMem<O, S>::onTimeTick() {

AERA/test_mem.h

@@ -101,8 +101,13 @@ template<class O, class S> class TestMem :
 
   /**
    * Override eject to check for (cmd set_velocity_y ...) and other implemented commands.
+   * \param command The command from the Replicode (cmd ...).
+   * \return The given command if it is executed as-is, or a new command object of the command
+   * that is actually executed. The program controller will make a fact from the command and
+   * inject it as the efferent copy. However, if the command is not executed, then return NULL
+   * and the program controller will put an anti-fact of the command in the mk.rdx reduction.
    */
-  virtual void eject(r_code::Code *command);
+  virtual r_code::Code* eject(r_code::Code *command);
 
   /**
    * This is called when runInDiagnosticTime() updates the tickTime. Just call

r_exec/mem.cpp

@@ -707,7 +707,7 @@ void _Mem::pushTimeJob(TimeJob *j) {
 void _Mem::eject(View *view, uint16 nodeID) {
 }
 
-void _Mem::eject(Code *command) {
+r_code::Code* _Mem::eject(Code *command) {
   // This is only for debugging
   /*
   uint16 function = (command->code(CMD_FUNCTION).atom_ >> 8) & 0x000000FF;
@@ -716,6 +716,7 @@ void _Mem::eject(Code *command) {
       //command->trace();
   }
   */
+  return NULL;
 }
 
 ////////////////////////////////////////////////////////////////

r_exec/mem.h

@@ -547,9 +547,16 @@ class r_exec_dll _Mem :
   // To be redefined by object transport aware subcalsses.
   virtual void eject(View *view, uint16 nodeID);
 
-  // From rMem to I/O device.
-  // To be redefined by object transport aware subcalsses.
-  virtual void eject(r_code::Code *command);
+  /**
+   * This is called by the program controller to eject a command from rMem to the 
+   * I/O device. This method should be redefined by object transport-aware subclasses.
+   * \param command The command from the Replicode (cmd ...).
+   * \return The given command if it is executed as-is, or a new command object of the command
+   * that is actually executed. The program controller will make a fact from the command and
+   * inject it as the efferent copy. However, if the command is not executed, then return NULL
+   * and the program controller will put an anti-fact of the command in the mk.rdx reduction.
+   */
+  virtual r_code::Code* eject(r_code::Code *command);
 
   virtual r_code::Code *_build_object(Atom head) const = 0;
   virtual r_code::Code *build_object(Atom head) const = 0;

r_exec/pgm_overlay.cpp

@@ -457,25 +457,31 @@ bool InputLessPGMOverlay::inject_productions() {
       }
     } else if (cmd[0].asOpcode() == Opcodes::Cmd) { // command to an external device, build a cmd object and send it.
 
-      Code *command = _Mem::Get()->build_object(cmd[0]);
-      cmd.copy(command, 0);
+      P<Code> command = _Mem::Get()->build_object(cmd[0]);
+      cmd.copy((Code*)command, 0);
 
-      _Mem::Get()->eject(command);
+      Code* executedCommand = _Mem::Get()->eject(command);
 
       // Build a fact of the command and inject it in stdin. Give the fact an uncertainty range since we don't know when
       // it will be executed. Otherwise a fact with zero duration may not overlap a fact, making predictions fail.
       // We offset the beginning of the uncertainty range by 2*GetTimeTolerance() (the same as SYNC_HOLD)
       // so that CTPX::reduce will not fail due to "cause in sync with the premise".
-      Code *fact = new Fact(command, now + 2 * Utils::GetTimeTolerance(), now + _Mem::Get()->get_sampling_period(), 1, 1);
-      View *view = new View(View::SYNC_ONCE, now, 1, 1, _Mem::Get()->get_stdin(), getView()->get_host(), fact); // SYNC_ONCE, sln=1, res=1,
-      _Mem::Get()->inject(view);
-      string mk_rdx_info = "";
+      P<Code> fact;
+      if (executedCommand) {
+        fact = new Fact(command, now + 2 * Utils::GetTimeTolerance(), now + _Mem::Get()->get_sampling_period(), 1, 1);
+        View *view = new View(View::SYNC_ONCE, now, 1, 1, _Mem::Get()->get_stdin(), getView()->get_host(), fact); // SYNC_ONCE, sln=1, res=1,
+        _Mem::Get()->inject(view);
+        string mk_rdx_info = "";
 #ifdef WITH_DEBUG_OID
-      if (mk_rdx)
-        // We don't know the mk.rdx OID yet, so use the debug OID.
-        mk_rdx_info = " mk.rdx(" + to_string(mk_rdx->get_debug_oid()) + "):";
+        if (mk_rdx)
+          // We don't know the mk.rdx OID yet, so use the debug OID.
+          mk_rdx_info = " mk.rdx(" + to_string(mk_rdx->get_debug_oid()) + "):";
 #endif
-      OUTPUT_LINE(IO_DEVICE_INJ_EJT, Utils::RelativeTime(Now()) << mk_rdx_info << " I/O device eject " << fact->get_oid());
+        OUTPUT_LINE(IO_DEVICE_INJ_EJT, Utils::RelativeTime(Now()) << mk_rdx_info << " I/O device eject " << fact->get_oid());
+      }
+      else
+        // The command wasn't executed. Set fact to an anti-fact of the original command and record in the mk_rdx.
+        fact = new AntiFact(command, after, before, 1, 1);
 
       if (mk_rdx) {