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.

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

1. One possible strategy is to use a nested function to create the property.

2. 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: solutions/wrapper2.py

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