装饰器实现的函数缓存器

func_cache.py

import time

def timer(func):
    def newFunc(*pargs, **kargs):
        start = time.time()
        back = func(*pargs, **kargs)
        print "Timer: %.2fs" % (time.time()-start)
        return back
    return newFunc

class FuncCache:
	def __init__(self, func):
		self.func = func
		self.cache = {}
		self.num = 0
	def cached(self, *pargs, **kargs):
		result = None
		if self.cache:
			for key in self.cache.keys():
				cache = self.cache[key]
				if len(cache) == 3 and set(cache[0]) == set(pargs) and cache[1] == kargs:
					result = cache[-1]
					break
		return result
	def __call__(self, *pargs, **kargs):
		result = self.cached(*pargs, **kargs)
		if result == None:
			result = self.func(*pargs, **kargs)
			self.num += 1
			self.cache[self.num] = [pargs, kargs, result]
			print 'calcing'
		return result

@timer
@FuncCache
def calc(*pargs):
	time.sleep(3)
	return sum(pargs)


if __name__ == '__main__':

	print calc(*range(100000))
	print calc(*range(100000))
	print calc(*range(1000000))
	print calc(*range(100000))