class openfisca_core.reforms.Reform(baseline)[source]

A modified TaxBenefitSystem

All reforms must subclass Reform and implement a method apply().

In this method, the reform can add or replace variables and call modify_parameters to modify the parameters of the legislation.


>>> from openfisca_core import reforms
>>> from openfisca_core.parameters import load_parameter_file
>>> def modify_my_parameters(parameters):
>>>     # Add new parameters
>>>     new_parameters = load_parameter_file(name='reform_name', file_path='path_to_yaml_file.yaml')
>>>     parameters.add_child('reform_name', new_parameters)
>>>     # Update a value
>>>     parameters.taxes.some_tax.some_param.update(period=some_period, value=1000.0)
>>>    return parameters
>>> class MyReform(reforms.Reform):
>>>    def apply(self):
>>>        self.add_variable(some_variable)
>>>        self.update_variable(some_other_variable)
>>>        self.modify_parameters(modifier_function = modify_my_parameters)

Make modifications on the parameters of the legislation.

Call this function in apply() if the reform asks for legislation parameter modifications.


modifier_function – A function that takes a ParameterNode and should return an object of the same type.