Refactor/mechanism/preprocess variable

Scripts/Scratch Pad.py

@@ -411,7 +411,7 @@ def __init__(self, error_value):
 #     print(projection.name)
 
 I = pnl.InputState(reference_value=[0,0,0])
-pnl.TransferMechanism(input_states=[I])
+pnl.TransferMechanism(name='TEMP', input_states=[I])
 
 p = pnl.MappingProjection()
 T = pnl.TransferMechanism(input_states=[{pnl.VARIABLE: [0, 0, 0], pnl.PROJECTIONS:[p]}])
@@ -530,10 +530,6 @@ def __init__(self, error_value):
 # my_control_mech = pnl.ControlMechanism(control_signals=[{pnl.MECHANISM: my_mech,
 #                                                          pnl.PARAMETER_STATES: [pnl.DRIFT_RATE, pnl.THRESHOLD]}])
 
-m = pnl.TransferMechanism(default_variable=[0, 0, 0])
-i = pnl.InputState(owner=m, variable=[0, 0, 0])
-T = pnl.TransferMechanism(input_states=[i])
-
 assert True
 
 # --------------------------------------------------------------------------------------------------

psyneulink/components/component.py

@@ -796,6 +796,8 @@ def __init__(self,
         # Used by run to store return value of execute
         self.results = []
 
+        default_variable, param_defaults = self._preprocess_variable(default_variable, size, param_defaults)
+
 
         # ENFORCE REQUIRED CLASS DEFAULTS
 
@@ -884,6 +886,12 @@ def __init__(self,
 
         self.init_status = InitStatus.INITIALIZED
 
+    def _preprocess_variable(self, variable, size, params):
+       # TODO:
+        # this is part of the hack in Mechanism to accept input_states as a way to instantiate default_variable for
+       # this release should be cleaned ASAP in default_variable overhaul
+        return variable, params
+
     def __repr__(self):
         return '({0} {1})'.format(type(self).__name__, self.name)
         #return '{1}'.format(type(self).__name__, self.name)

psyneulink/components/mechanisms/mechanism.py

@@ -1097,69 +1097,6 @@ def __init__(self,
             raise MechanismError("Direct call to abstract class Mechanism() is not allowed; "
                                  "use a subclass")
 
-        # TODO:
-        # this is a hack to accept input_states as a way to instantiate default_variable for this release
-        # should be cleaned ASAP in default_variable overhaul
-        default_variable_from_input_states = None
-
-        def spec_incompatible_with_default_error(spec_variable, default_variable):
-            return MechanismError(
-                'default variable determined from the specified input_states spec ({0}) '
-                'is not compatible with the specified default variable ({1})'.format(
-                    spec_variable, default_variable
-                )
-            )
-
-        # handle specifying through params dictionary
-        try:
-            default_variable_from_input_states, input_states_variable_was_specified = \
-                self._parse_arg_input_states(params[INPUT_STATES])
-        except (TypeError, KeyError):
-            pass
-
-        if default_variable_from_input_states is None:
-            # fallback to standard arg specification
-            default_variable_from_input_states, input_states_variable_was_specified = \
-                self._parse_arg_input_states(input_states)
-
-        if default_variable_from_input_states is not None:
-            if variable is None:
-                if size is None:
-                    variable = default_variable_from_input_states
-                else:
-                    if input_states_variable_was_specified:
-                        size_variable = self._handle_size(size, None)
-                        if iscompatible(size_variable, default_variable_from_input_states):
-                            variable = default_variable_from_input_states
-                        else:
-                            raise MechanismError(
-                                'default variable determined from the specified input_states spec ({0}) '
-                                'is not compatible with the default variable determined from size parameter ({1})'.
-                                    format(default_variable_from_input_states, size_variable,
-                                )
-                            )
-                    else:
-                        # do not pass input_states variable as default_variable, fall back to size specification
-                        pass
-            else:
-                compatible = iscompatible(self._parse_arg_variable(variable), default_variable_from_input_states)
-                if size is None:
-                    if input_states_variable_was_specified:
-                        if compatible:
-                            variable = default_variable_from_input_states
-                        else:
-                            raise spec_incompatible_with_default_error(default_variable_from_input_states, variable)
-                    else:
-                        pass
-                else:
-                    if input_states_variable_was_specified:
-                        if compatible:
-                            variable = default_variable_from_input_states
-                        else:
-                            raise spec_incompatible_with_default_error(default_variable_from_input_states, variable)
-                    else:
-                        pass
-
         # IMPLEMENT **kwargs (PER State)
 
 
@@ -1268,6 +1205,77 @@ def spec_incompatible_with_default_error(spec_variable, default_variable):
         self.processes = {}
         self.systems = {}
 
+
+    def _preprocess_variable(self, default_variable, size, params):
+
+        # TODO:
+        # this is a hack to accept input_states as a way to instantiate default_variable for this release
+        # should be cleaned ASAP in default_variable overhaul
+        default_variable_from_input_states = None
+
+        def spec_incompatible_with_default_error(spec_variable, local_default_variable):
+            return MechanismError(
+                'default variable determined from the specified input_states spec ({0}) '
+                'is not compatible with the specified default variable ({1})'.format(
+                    spec_variable, local_default_variable
+                )
+            )
+
+        # handle specifying through params dictionary
+        try:
+            default_variable_from_input_states, input_states_variable_was_specified = \
+                self._parse_arg_input_states(params[INPUT_STATES])
+        except (TypeError, KeyError):
+            pass
+
+        if default_variable_from_input_states is None:
+            # fallback to standard arg specification
+            default_variable_from_input_states, input_states_variable_was_specified = \
+                self._parse_arg_input_states(self.input_states)
+
+        if default_variable_from_input_states is not None:
+            if default_variable is None:
+                if size is None:
+                    default_variable = default_variable_from_input_states
+                else:
+                    if input_states_variable_was_specified:
+                        size_variable = self._handle_size(size, None)
+                        if iscompatible(size_variable, default_variable_from_input_states):
+                            variable = default_variable_from_input_states
+                        else:
+                            raise MechanismError(
+                                'default variable determined from the specified input_states spec ({0}) '
+                                'is not compatible with the default variable determined from size parameter ({1})'.
+                                    format(default_variable_from_input_states, size_variable,
+                                )
+                            )
+                    else:
+                        # do not pass input_states variable as default_variable, fall back to size specification
+                        pass
+            else:
+                compatible = iscompatible(self._parse_arg_variable(default_variable),
+                                          default_variable_from_input_states)
+                if size is None:
+                    if input_states_variable_was_specified:
+                        if compatible:
+                            variable = default_variable_from_input_states
+                        else:
+                            raise spec_incompatible_with_default_error(default_variable_from_input_states,
+                                                                       default_variable)
+                    else:
+                        pass
+                else:
+                    if input_states_variable_was_specified:
+                        if compatible:
+                            variable = default_variable_from_input_states
+                        else:
+                            raise spec_incompatible_with_default_error(default_variable_from_input_states,
+                                                                       default_variable)
+                    else:
+                        pass
+
+        return default_variable, params
+
     def _parse_arg_variable(self, variable):
         '''
         Takes user-inputted argument **variable** and returns an instance_defaults.variable-like