坐标继承变更

inherited_point.py

class Point(dict):

    def __init__(self, x, y):
        self['x'] = x
        self['y'] = y

    def __getattr__(self, attr):
        return self[attr]() if callable(self[attr]) else self[attr]

    def __setattr__(self, attr, value):
        self[attr] = value

    def __add__(self, other):
        return Point(lambda: self.x + other.x, lambda: self.y + other.y)

    def __sub__(self, other):
        return Point(lambda: self.x - other.x, lambda: self.y - other.y)
    
    def __str__(self):
        return f'Point({self.x:.2f}, {self.y:.2f})'

if __name__ == "__main__":
    a = Point(1, 2)
    print('a', a)       # Point(1.00, 2.00)
    print('a.x', a.x)   # 1
    a.x = 3
    print('a', a)       # Point(3.00, 2.00)
    print('a.x', a.x)   # 3
    b = Point(0, 6)
    print('b', b)       # Point(0.00, 6.00)
    c = a + b - Point(100, 100)
    print('c', c)       # Point(-97.00, -92.00)
    b.y = 1000
    print('c', c)       # Point(-97.00, -92.00)