運用staticmethod裝飾器的簡單方式

from math import sqrt


class Triangle(object):

    def __init__(self, a, b, c):
        self._a = a
        self._b = b
        self._c = c

    @staticmethod
    def is_valid(a, b, c):
        return a + b > c and b + c > a and a + c > b

    def perimeter(self):
        return self._a + self._b + self._c

    def area(self):
        half = self.perimeter() / 2
        return sqrt(half *
                    (half - self._a) *
                    (half - self._b) *
                    (half - self._c))


def main():
    a, b, c = 3, 4, 5
    # 靜態方法和類方法都是通過給類發消息來調用的
    if Triangle.is_valid(a, b, c):
        t = Triangle(a, b, c)
        print("周長：", t.perimeter())
        # 也可以通過給類發消息來調用對象方法但是要傳入接收消息的對象作爲參數
        # print(Triangle.perimeter(t))
        print("面積：", t.area())
        # print(Triangle.area(t))
    else:
        print('無法構成三角形.')


if __name__ == '__main__':
    main()

輸出：

from math import sqrt


class Triangle(object):

    def __init__(self, a, b, c):
        self._a = a
        self._b = b
        self._c = c

    @staticmethod
    def is_valid(a, b, c):
        return a + b > c and b + c > a and a + c > b

    def perimeter(self):
        return self._a + self._b + self._c

    def area(self):
        half = self.perimeter() / 2
        return sqrt(half *
                    (half - self._a) *
                    (half - self._b) *
                    (half - self._c))


def main():
    a, b, c = 3, 4, 5
    # 靜態方法和類方法都是通過給類發消息來調用的
    if Triangle.is_valid(a, b, c):
        t = Triangle(a, b, c)
        print("周長：", t.perimeter())
        # 也可以通過給類發消息來調用對象方法但是要傳入接收消息的對象作爲參數
        # print(Triangle.perimeter(t))
        print("面積：", t.area())
        # print(Triangle.area(t))
    else:
        print('無法構成三角形.')


if __name__ == '__main__':
    main()