print(delete_resource(user, 1)) # 成功执行 通过组合不同的权限检查函数,multi_permission_check装饰器确保所有条件都满足后才执行被装饰的函数,增加了权限控制的灵活性和安全性。 6、重试装饰器 在不稳定或网络依赖的环境中,重试机制是处理临时故障的有效策略。本章将逐步构建重试装饰器 ,从基础到高级,确保操作...
NewType类型,声明一个不同的类型而又不实际执行创建新类型,在运行时,将返回一个仅返回其参数的虚拟函数: from typing import NewType UserId = NewType('UserId', int) def name_by_id(user_id: UserId) -> str: ... UserId('user') # Fails type check ...
它必须是一个异常的实例或者是异常的类(也就是 Exception 的子类)。大多数的异常的名字都以"Error"结尾,所以实际命名时尽量跟标准的异常命名一样。 #1.用户自定义异常类型 class TooLongExceptin(Exception): "this is user's Exception for check the length of name " def __init__(self,leng): self.len...
Because control jumps immediately to a handler when an exception occurs, there's no need to instrument all your code to guard for errors. Moreover, because Python detects errors automatically, your code usually doesn’t need to check for errors in the first place. The upshot is that exceptio...
exception webbrowser.Error, 当浏览器控件发生错误是会抛出这个异常 webbrowser有以下方法: webbrowser.open(url[, new=0[, autoraise=1]]) 这个方法是在默认的浏览器中显示url, 如果new = 0, 那么url会在同一个浏览器窗口下打开,如果new = 1, 会打开一个新的窗口,如果new = 2, 会打开一个新的tab, ...
assert for exception trap def main(s): n = int(s) assert n != 0, "n is zero" return 10/n main(0) Return: "AssertionError: n is zero s" Checking the type if isinstance(p, tuple): # this is good if type(p) == tuple: # this is bad ...
class InvalidAgeError(Exception): """年龄无效时抛出的异常""" def __init__(self, age, message="年龄必须在 0-150 之间"): self.age = age self.message = message super().__init__(self.message) def check_age(age): if age < 0 or age > 150: ...
catch a zero division exception 这里指定了一个除零异常并正常捕获。 当然,我们也可以进一步获取到异常并输出异常的信息: try: a =2/0exceptZeroDivisionErrorase:print("catch a zero division exception")print(e) 输出 catch a zero division exception ...
arcpy.env.overwriteOutput =Truefc = arcpy.GetParameterAsText(0)try:# Check that the input has featuresresult = arcpy.GetCount_management(fc)ifint(result[0]) >0: arcpy.FeatureToPolygon_management( fc, os.path.join(os.path.dirname(fc),'out_poly.shp'))else:# Raise custom exceptionraiseNoFe...
check_key('type', dic_customers) Output: The following output will appear after executing the above script. The value of the ‘customer_id’ key has been printed, and the error message has been printed for the ‘type’ key. Conclusion: Different ways to avoid the KeyError exception that oc...