__defaults__[0][:] = [] >>> function() [1] >>> function.__defaults__ ([1],) 不过,你最好别这么干(修改一些你不了解的的东西,比如私有变量或者系统变量,会导致一些神奇的后果)。 另一个对默认参数进行重置的方法就是重新执行同样的 def 函数定义语句,也即,把 function 定义再执行一次。当你这...
Default parameter values are evaluated when the function definition is executed.This means that the expression is evaluated once, when the function is defined, and that that same “pre-computed” value is used for each call. This is especially important to understand when a default parameter is ...
Default parameter values are evaluated when the function definition is executed. 也就是说默认函数参数是在写def时就已经被赋值(引用)了! 这样你可以把默认参数理解成function对象的一个类似于'member variable'之类的东西来对待!! 这也就是说如果默认参数是可变的,如果function改变了这个参数(append or something ...
If python function default input is mutable, calling the function will change on top of. defmutable_parameter(lst=[]):iflstisNone:lst=[]lst.append(1)returnlstprint(mutable_parameter())print(mutable_parameter())[1][1]use'lst=None'instead! Modifying while iterating First make sure modifying ...
The following example shows how to use a default parameter value.If we call the function without argument, it uses the default value:Example def my_function(country = "Norway"): print("I am from " + country) my_function("Sweden")my_function("India")my_function()my_function("Brazil") ...
https://docs.python.org/2/reference/compound_stmts.html#function-definitions 其中有下面一段 "Default parameter values are evaluated when the function definition is executed. This means that the expression is evaluated once, when the function is defined, and that the same “pre-computed” value is...
def functionName(parameter1,parameter2): suite 2、一些相关的概念 def是一个可执行语句 因此可以出现在任何能够使用语句的地方,甚至可以嵌套于其它语句中,例如if或while中 def创建了一个对象并将其赋值给一个变量名(即函数名上面语法中的functionName) return用于返回结果对象,其为可选,无return语句的函数,自动...
Function+bool has_parameters() 旅行图如下: Default Argument Function --> Default Argument Default Argument --> Function Variable Argument Function --> Variable Argument Variable Argument --> Function Inspect Module Function --> Inspect Module ...
if FunctionSignature.signature_downgrade: self.name = name self.args = "*args, **kwargs" self.rtype = "typing.Any" lvl = logging.WARNING if FunctionSignature.ignore_invalid_signature else logging.ERROR logger.log(lvl, "Generated stubs signature is degraded to `(*args, **kwargs) ...
Only one value is passed during the function call. So, according to the positional argument2is assigned to argumenta, and the default value is used for parameterb. 3. add_numbers() No value is passed during the function call. Hence, default value is used for both parametersaandb. ...