Strategy Pattern

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객체의 행위를 바꾸고 싶은데 직접 수정하지 않는 패턴

from abc import ABC, abstactmethod
 
 
class FilterStrategy(ABC):
	@abstactmethod
	def remove_value(self, value):
		pass
 
class RemoveNegativeStrategy(FilterStrategy):
	def remove_value(self, value):
		return value < 0
 
class RemoveOddStrategy(FilterStrategy):
	def remove_value(self, value):
		return abs(value) % 2
 
class Values:
	def __init__(self, values):
		self.values = values
 
	def filter(self, strategy):
		result = []
		for number in self.values:
			if not strategy.remove_value(number):
				result.append(number)
 
			return result
 
values = Values([-2, -7, 2, 0, 4, 10])
 
print(values.filter(RemoveOddStrategy()))
print(values.filter(RemoveNegativeStrategy()))