Add __dir__ method to Equation and ParameterProxy.

This supports attributes completion in IPython.

Author: pavoljuhas

diffpy/srfit/equation/equationmod.py

@@ -116,6 +116,20 @@ def __getattr__(self, name):
             raise AttributeError("No argument named '%s' here" % name)
         return argdict[name]
 
+
+    # Ensure there is no __dir__ override in the base class.
+    assert (getattr(Operator, '__dir__', None) is
+            getattr(object, '__dir__', None))
+
+
+    def __dir__(self):
+        "Return sorted list of attributes for this object."
+        rv = set(dir(type(self)))
+        rv.update(self.__dict__.keys() + self.argdict.keys())
+        rv = sorted(rv)
+        return rv
+
+
     def setRoot(self, root):
         """Set the root of the Literal tree.
 

diffpy/srfit/fitbase/parameter.py

@@ -170,6 +170,21 @@ def __getattr__(self, attrname):
         par = object.__getattribute__(self, 'par')
         return getattr(par, attrname)
 
+
+    # Ensure there is no __dir__ override in the base classes.
+    assert (getattr(_parameter_interface, '__dir__', None) is
+            getattr(Validatable, '__dir__', None) is
+            getattr(object, '__dir__', None))
+
+
+    def __dir__(self):
+        "Return sorted list of attributes for this object."
+        rv = set(dir(type(self)))
+        rv.update(self.__dict__.keys() + dir(self.par))
+        rv = sorted(rv)
+        return rv
+
+
     value = property( lambda self: self.par.getValue(),
             lambda self, val: self.par.setValue(val) )