def statictypes(a):
    def b(a,b,c):
        if b in a and not isinstance(c,a[b]): raise TypeError('{} should be {},not {}'.format(b,a[b],type(c)))
        return c
    return __import__('functools').wraps(a)(lambda *c: b(a.__annotations__,'return',a(*(b(a.__annotations__,*d) for d in zip(a.__code__.co_varnames,c)))))

@statictypes
def isallinstance(iterable: object,class_or_type_or_tuple: (type,tuple)) -> bool:
    """isallinstance(iterable,class_or_type_or_tuple) -> bool

    Return whether all items in an iterable are instances of a class or of a
    subclass thereof. With a type as second argument,return whether that is
    all items' type. The form using a tuple,isallinstance(x,(A,B,...)),is a shortcut for any(isallinstance(x,y) for y in (A,...)).
    """
    return all(isinstance(item,class_or_type_or_tuple) for item in iterable)

以下显示了与Python解释器的对话,并突出显示出现的错误.生成TypeError,但不生成预期的TypeError.虽然发电机很好,但现在它们都失败了.

>>> isallinstance(range(1000000),int)
True
>>> isallinstance(range(1000000),(int,float))
True
>>> isallinstance(range(1000000),[int,float])
Traceback (most recent call last):
  File "<pyshell#26>",line 1,in <module>
    isallinstance(range(1000000),float])
  File "C:\Users\schappell\Downloads\test.py",line 5,in <lambda>
    return __import__('functools').wraps(a)(lambda *c: b(a.__annotations__,c)))))
TypeError: isallinstance() argument after * must be a sequence,not generator

可以重写statictypes函数,并重新定义和包装isallinstance函数.最简单的解决方案是将statictypes中的generatior重写为列表理解.

def statictypes(a):
    def b(a,a(*[b(a.__annotations__,c)])))

之后,一旦从头开始重新创建,isallinstance将按预期开始工作. TypeError指出第二个参数的错误是正确生成的.

>>> isallinstance(range(1000000),float])
Traceback (most recent call last):
  File "<pyshell#29>",c)])))
  File "C:\Users\schappell\Downloads\test.py",in <listcomp>
    return __import__('functools').wraps(a)(lambda *c: b(a.__annotations__,line 3,in b
    if b in a and not isinstance(c,type(c)))
TypeError: class_or_type_or_tuple should be (<class 'type'>,<class 'tuple'>),not <class 'list'>

问题：

>为什么第一个功能与发生器somtimes工作,其他时间失败？
>为什么生成器不被视为序列(因为它生成序列)？
>为什么当发电机显然在某些时候工作时需要一个序列？