🐍Python深化(Decorator)

デコレーション特性

装飾の例

import time

def perf_clock(func):

    def perf_clocked(*args):
        # 시작시간 
        st = time.perf_counter()
        result = func(*args)
        # 종료시간 
        et = time.perf_counter() - st 
        # 함수명 
        name = func.__name__
        # 매개변수 
        arg_str = ','.join(repr(arg) for arg in args)
        # 출력 
        print('[%0.5fs] %s(%s) -> %r' % (et, name, arg_str, result))
        return result
    return perf_clocked

def time_func(seconds):
    time.sleep(seconds)


def sum_func(*numbers):
    return sum(numbers)


def fact_func(n):
    return 1 if n < 2 else n * fact_func(n-1)

装飾品を使用しない例

non_deco1 = perf_clock(time_func)
non_deco2 = perf_clock(sum_func)
non_deco3 = perf_clock(fact_func)


non_deco1(2)
# [2.00034s] time_func(2) -> None
non_deco2(100, 200, 300, 400, 500) 
# [0.00000s] sum_func(100,200,300,400,500) -> 1500
non_deco3(10)
# [0.00001s] fact_func(10) -> 3628800

アクセサリーの使用例

@perf_clock
def time_func(seconds):
    time.sleep(seconds)

@perf_clock
def sum_func(*numbers):
    return sum(numbers)

@perf_clock
def fact_func(n):
    return 1 if n < 2 else n * fact_func(n-1)

time_func(2)
# [2.00027s] time_func(2) -> None
sum_func(10,20,30,40,50)
# [0.00000s] sum_func(10,20,30,40,50) -> 150
fact_func(10)
# [0.00000s] fact_func(1) -> 1
# [0.00001s] fact_func(2) -> 2
# [0.00002s] fact_func(3) -> 6
# [0.00005s] fact_func(4) -> 24
# [0.00005s] fact_func(5) -> 120
# [0.00006s] fact_func(6) -> 720
# [0.00007s] fact_func(7) -> 5040
# [0.00008s] fact_func(8) -> 40320
# [0.00009s] fact_func(9) -> 362880
# [0.00010s] fact_func(10) -> 3628800

アクセサリーの説明