python global variable in class

When we create a module of our own, the module itself comes with several global variables, which are present in each file.View py Global variables for the current file[[email protected] ~]# echo ' Print (VARs ()) ' > scripts.py [[email protected] ~]# python scripts.py {' __builtins__ ': Default global variables

Python refers to the order of variables: the current scope local variable-> outer scope variable-> the global variable in the current module->python built-in variable One,

This article mainly introduces how to implement cross-file global variables in python. For more information about how to use Python to compile applications, sometimes the same global variable is transferred between multiple files. This article provides the following solution

1. What is a local variableA local variable is a variable that has a local effect and is defined inside a function. The scope is only within the function, the variables outside the function is not affected, that is, the same name function, if not in the function to do the global DeclarationThen there's no effect on the outside of the function.1x ="Alex"2 3 deffun

Python global variables do not conform to the relevant rules of parameter passing, so many people do not want to use them frequently unless constants are defined. We will discuss global variables and find the hidden tips. I hope you will gain some gains through this article. The program is roughly like this: CONSTANT=0 defmodifyConstant(): printCONST

Analysis of global usage instances in python This example describes global usage in python. Share it with you for your reference. The specific analysis is as follows: 1. global --- define a variable as a

that the function can access global variables. Therefore, the problem is that, because the variable CONSTANT is modified inside the function, Python considers CONSTANT as a local variable, and print CONSTANT is before CONSTANT + = 1, this error will certainly occur. So, how should we access and modify

Look at the code first:Code One:#!/usr/bin/python#coding:utf8x = def test ():p rint ' x= ', xtest ()Code One execution Result:x = 20We have a slight modification on the basis of code one.Code two:x = def test ():p rint ' x= ', xx = 2 print ' Change X to ', Xtest ()Code Two execution results:X=traceback (most recent): file "D:\Demo\testGlobal.py", line to Parsing the problem: we tried to reassign X to 2 in line 4th, and because of the scope of the

num = 5def func ():num + = 1Print (num)Print (num)Output:unboundlocalerror:local variable ' num ' referenced before assignmentTranslation: Local variable error: the variable "num" is not defined and is applied. This proves once again that a local variable is defined, not a global