python 类型注解

def add(x,y):
    return x+y
print(add(4,5))
print(add(‘hello‘,‘world‘))
print(add(4,‘hello‘)) #报错，TypeError: unsupported operand type(s) for +: ‘int‘ and ‘str‘

def add(x,y):
    """
    :param x:int
    :param y:int
    :return:int
    """
    return x+y
print(help(add))

def add(x:int,y:int)->int:
    """
    :param x:int
    :param y:int
    :return:int
    """
    return x+y
print(help(add))
print(add(4,5))
print(add("jax","zhai"))   #在pycharm里参数是灰色

import inspect
def add(x:int,y:int,*args,**kwargs)->int:
    return x+y
sig =  inspect.signature(add)
print(sig,type(sig)) #获取签名
print(‘params :‘,sig.parameters) #OrderedDict
print(‘return :‘,sig.return_annotation) #返回值类型
print(sig.parameters[‘y‘], type(sig.parameters[‘y‘]))
print(sig.parameters[‘x‘].annotation)
print(sig.parameters[‘args‘])
print(sig.parameters[‘args‘].annotation)
print(sig.parameters[‘kwargs‘])
print(sig.parameters[‘kwargs‘].annotation)

inspect.isfunction(add) #是不是函数
inspect.ismethod(add) #是不是类方法
inspect.isgenerator(add) #是不是生成器
inspect.isclass(add) #是不是类
inspect.ismodule(add) #是不是模块
inspect.isbuiltin(add) #是不是内建对象

import inspect
def add(x:int,y:int,*args,**kwargs)->int:
    return x+y
sig =  inspect.signature(add)
print(sig)
print(‘params : ‘, sig.parameters)
print(‘return : ‘, sig.return_annotation)
print(‘~~~~~~~~~~~~~~~~‘)
for i,item in enumerate(sig.parameters.items()):
    name,param = item
    print(i+1,name,param.annotation,param.kind,param.default)
    print(param.default is param.empty, end = ‘\n\n‘)

def add(x,y:int=7) -> int:
    return x + y

def check(fn):
    def wrapper(*args,**kwargs):
        sig = inspect.signature(fn)
        params = sig.parameters
        values = list(params.values())
        #print(values)
        for i,p in enumerate(args):
           # print(i,p)
            params = values[i]
            #print(params.annotation,params.empty)
            if params.annotation is not params.empty and not isinstance(p,params.annotation):
                print(p,‘!==‘,values[i].annotation)
        for k,v in kwargs.items():
            if sig.parameters[k].annotation is not inspect._empty and not isinstance(v,sig.parameters[k].annotation):
                print(k,v,‘!===‘,sig.parameters[k].annotation)
        return fn(*args,**kwargs)
    return wrapper
@check
def add(x,y:int=7) -> int:
    return x + y
#print(add(20,10))
print(add(20,y=10))
print(add(y=10,x=20))