Add a method to test the existence of a signal.

CMakeLists.txt

@@ -39,7 +39,7 @@ SET(PKG_CONFIG_ADDITIONAL_VARIABLES plugindir ${PKG_CONFIG_ADDITIONAL_VARIABLES}
 SETUP_PROJECT()
 
 # Trigger dependency to dynamic-graph.
-ADD_REQUIRED_DEPENDENCY("dynamic-graph >= 1.0")
+ADD_REQUIRED_DEPENDENCY("dynamic-graph >= 2.5.5-6")
 
 # Add dependency toward dynamic graph library in pkg-config file.
 PKG_CONFIG_APPEND_LIBS("dynamic-graph-python")

src/dynamic-graph-py.cc

@@ -48,6 +48,7 @@ namespace dynamicgraph {
       extern PyObject* display(PyObject* self, PyObject* args);
       extern PyObject* display(PyObject* self, PyObject* args);
       extern PyObject* getName(PyObject* self, PyObject* args);
+      extern PyObject* hasSignal(PyObject* self, PyObject* args);
       extern PyObject* getSignal(PyObject* self, PyObject* args);
       extern PyObject* listSignals(PyObject* self, PyObject* args);
       extern PyObject* executeCommand(PyObject* self, PyObject* args);
@@ -179,6 +180,8 @@ static PyMethodDef dynamicGraphMethods[] = {
    "print an Entity C++ object"},
   {"entity_get_name", dynamicgraph::python::entity::getName, METH_VARARGS,
    "get the name of an Entity"},
+  {"entity_has_signal", dynamicgraph::python::entity::hasSignal, METH_VARARGS,
+   "return True if the entity has a signal with the given name"},
   {"entity_get_signal", dynamicgraph::python::entity::getSignal, METH_VARARGS,
    "get signal by name from an Entity"},
   {"entity_list_signals", dynamicgraph::python::entity::listSignals,

src/dynamic_graph/entity.py

@@ -107,6 +107,12 @@ class Entity (object) :
         signalPt = wrap.entity_get_signal(self.obj, name)
         return signal_base.SignalBase(name = "", obj = signalPt)
 
+    def hasSignal(self, name) :
+        """
+        Indicates if a signal with the given name exists in the entity
+        """
+        return wrap.entity_has_signal(self.obj, name)
+
     def displaySignals(self) :
         """
         Print the list of signals into standard output: temporary.

src/entity-py.cc

@@ -113,7 +113,40 @@ namespace dynamicgraph {
       }
 
       /**
-	 \brief Get a signal by name
+         \brief Check if the entity has a signal with the given name
+      */
+      PyObject * hasSignal(PyObject* /*self*/, PyObject* args)
+      {
+        char *name = NULL;
+        PyObject* object = NULL;
+        void* pointer = NULL;
+
+	if (!PyArg_ParseTuple(args, "Os", &object, &name))
+	  Py_RETURN_FALSE;
+
+	if (!PyCObject_Check(object)) {
+	  PyErr_SetString(PyExc_TypeError,
+			  "function takes a PyCObject as argument");
+	  Py_RETURN_FALSE;
+	}
+
+	pointer = PyCObject_AsVoidPtr(object);
+	Entity* entity = (Entity*)pointer;
+
+	bool hasSignal = false;
+	try {
+	  hasSignal = entity->hasSignal(std::string(name));
+	} CATCH_ALL_EXCEPTIONS();
+
+	if (hasSignal)
+	  Py_RETURN_TRUE;
+	else
+	  Py_RETURN_FALSE;
+      }
+
+
+      /**
+         \brief Get a signal by name
       */
       PyObject* getSignal(PyObject* /*self*/, PyObject* args)
       {