strategy.py

"""http://stackoverflow.com/questions/963965/how-is-this-strategy-pattern-written-in-python-the-sample-in-wikipedia"""

import types  


class StrategyExample:

    def __init__(self, func=None):         
        self.name = "Strategy Example 0"         
        if func:
            self.execute = types.MethodType(func, self)      

    def execute(self):         
        print(self.name)   


def executeReplacement1(self):
    print(self.name + " from execute 1")   


def executeReplacement2(self):
    print(self.name + " from execute 2")  


if __name__ == "__main__":
    strat0 = StrategyExample()     

    strat1 = StrategyExample(executeReplacement1)     
    strat1.name = "Strategy Example 1"     

    strat2 = StrategyExample(executeReplacement2)     
    strat2.name = "Strategy Example 2"      

    strat0.execute()     
    strat1.execute()     
    strat2.execute()