有什么方法可以缩短具有相似语句但不同 returns 的属性？

Question

class....

    @property
    def degrees(self):
        hem, degs, mins, secs = self._correction()
        return degs

    @property
    def minutes(self):
        hem, degs, mins, secs = self._correction()
        return mins

    @property
    def seconds(self):
        hem, degs, mins, secs = self._correction()
        return secs

我在想 def 可以截断为：

@property
def hemisphere, degrees, minutes, seconds(self):
    hem, degs, mins, secs = self._correction()
    return hem, degs, mins, secs

所以当我调用 'hemisphere' 时它会 return 下摆值等等。

PS。我知道我在后者的 return 语句是错误的。我希望你明白我的意思。

Answer 1

您可以覆盖 __getattr__ 方法

def __getattr__(self, item):
    values = ["hemisphere", "degrees", "minutes", "seconds"]
    if item in values:
        return self._correction()[values.index(item)]
    raise AttributeError(f"'{self.__class__.__name__}' object has no attribute '{item}'")

Answer 2

有很多方法可以缩短它，我会写另一个辅助函数：

from functools import wraps

def unpack(rng, fn, propertize=False):
    for i in rng:
        @wraps(fn)
        def wrapper(*args, __i=i, **kwargs):
            return fn(*args, **kwargs)[i]
        yield property(wrapper) if propertize else wrapper

...

class Something:
    hemisphere, degrees, minutes, seconds = unpack(
        range(4), Something._correction, propertize=True
    )

Answer 3

正如@xjcl 评论的那样，在简单的基础上优先于看似不必要的 complication/obfuscation:

class....

    @property
    def degrees(self):
        return self._correction()[1]

    @property
    def minutes(self):
        return self._correction()[2]

    @property
    def seconds(self):
        return self._correction()[3]

有什么方法可以缩短具有相似语句但不同 returns 的属性？

Is there any way I can shorten properties with similar statements but different returns?

python

class-properties