number= 10printnumber 就会出现下面的错误提示: UnboundLocalError: local variable 'number' referenced before assignment 在python2.7 和 python3.4上测试, 出现同样的上述结果.
In Python, we can declare variables in three different scopes: local scope, global, and nonlocal scope. A variable scope specifies the region where we can access avariable. For example, defadd_numbers():sum =5+4 Here, thesumvariable is created inside thefunction, so it can only be acces...
What is Python Variable Scope? The scope of a variable inpythonis that part of the code where it is visible. Actually, to refer to it, you don’t need to use any prefixes then. Types of Python Variable Scope There are 4 types of Variable Scope inPython, let’s discuss them one by ...
此文主要讨论和总结一下,Python中的变量的作用域(variable scope)。 目的在于,通过代码,图解,文字描述,使得更加透彻的了解,Python中的变量的作用域; 以避免,在写代码过程中,由于概念不清晰而导致用错变量,导致代码出错和变量含义错误等现象。 如有错误,欢迎指正。 解释Python中变量的作用域 Python变量作用域的解释之...
除了在函数内部定义变量,Python 还允许在所有函数的外部定义变量,这样的变量称为全局变量(Global Variable)。 和局部变量不同,全局变量的默认作用域是整个程序,即全局变量既可以在各个函数的外部使用,也可以在各函数内部使用。 定义全局变量的方式有以下 2 种: 在函数体外定义的变量,一定是全局变量,例如: ...
Local Scope Whenever you define a variable within a function, its scope lies ONLY within the function. It is accessible from the point at which it is defined until the end of the function and exists for as long as the function is executing (Source). Which means its value cannot be change...
5 print(x*2) 10 新的值会覆盖掉旧的值 新值的数据类型不必与旧值相同 y = 10 print(y - 2) 8 y = True print(y) True 变量命名规则: 必须以字母或下划线(_)开头 命名可由字母、数字和下划线组成 大小写敏感 尽量避免使用保留字命名 numberOfRabbits = 40 courseIs15112 = True ...
Unlock This Lesson This lesson is for members only.Join us and get access to thousands of tutorials and a community of expert Pythonistas. Unlock This Lesson Variable Scope Navigating Namespaces and Scope in PythonJohan Vergeer01:03 Mark as Completed ...
Python Variable Scope Although there are various unique namespaces defined, we may not be able to access all of them from every part of the program. The concept of scope comes into play. A scope is the portion of a program from where a namespace can be accessed directly without any prefix...
The local variable can be accessed from a function within the function: defmyfunc(): x =300 defmyinnerfunc(): print(x) myinnerfunc() myfunc() Try it Yourself » Global Scope A variable created in the main body of the Python code is a global variable and belongs to the global scope...