Python——定义带参数的装饰器

可以看成生产装饰器的工厂，每次调用typeassert,返回一个特定的装饰器，然后用它去修饰其他函数。

from inspect import signature
def typeassert(*ty_args, **ty_kargs):
    def decoraror(func):
        # func ->a,b
        # d = {'a':int, 'b':str}
        sig = signature(func)
        btypes = sig.bind_partial(*ty_args, **ty_kargs).arguments
        def wrapper(*args, **kargs):
            # arg in d,instance(arg,d[arg])
            for name, obj in sig.bind(*args, **kargs).arguments.items():
                if name in btypes:
                    if not isinstance(obj, btypes[name]):
                      raise TypeError('"%s" must be "%s"'% (name, btypes[name]))

            return func(*args, **kargs)
        return wrapper
    return decoraror
@typeassert(int, str, list)
def f(a, b, c):
    print(a, b, c)

f(1, 'abc', [1, 2, 3])
f(1, 22, [1, 2, 3])    #会报错