Frame Hack Recipe: Generating properties on a wrapper class
===========================================================

Step 2
------
Implement the ``properties`` function, using a frame hack. This time, you are not allowed to use the ``eval`` function.s

.. sourcecode:: python

    import sys
    from employee import Employee

    def properties(**kwargs):
        """Implement this function"""
        
    class PyEmployee(object):
        def __init__(self, **kwargs):
            self.e = Employee()
            for k, v in kwargs.items():
                setattr(self, k, v)

        properties(
            given  = 'GivenName',
            family = 'FamilyName',
            birth =  'DateOfBirth',
        )

    e = PyEmployee(given='Feihong', family='Hsu', birth='2007-11-15')
    print e.given, e.e.GetGivenName()

    e.given = 'Horatio'     # change given name through the property
    print e.given, e.e.GetGivenName()

    e.family = 'Kodiak'
    print e.family, e.e.GetFamilyName()

    e.birth = '2009-12-23'
    print e.birth, e.e.GetDateOfBirth()

Expected output::

    Feihong Feihong
    Horatio Horatio
    Kodiak Kodiak
    2009-12-23 2009-12-23    

Hints:

.. class:: hintlist

#. One possible strategy is to use a nested function to create the property.
#. Your nested function might look like this::

    def get_property(name):
        def get(self):
            return getattr(self.e, 'Get'+name)()
        
        def set(self, value):
            getattr(self.e, 'Set'+name)(value)

        return property(get, set)
    
Solution: `wrapper2.py <solutions/wrapper2.py>`_

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