Python globals() Function
Python3 Built-in Functionsglobals()It is a built-in function in Python used to return the dictionary of variables in the current global scope.
globals()Returns a dictionary containing all global variables of the current module. This dictionary contains all imported modules, defined functions, classes, and global variables.
Word Definition： globals 意为"全局的"，表示全局作用域中的变量。
Basic Syntax and Parameters
Syntax Format
globals()
Parameter Description
- No parameters
Function Description
- Return Value: Returns a dictionary containing variables in the global scope.
Example
Example 1: View Global Variables
Example
# Define some global variables
global_var = 100
global_list = [1, 2, 3]
import math
import os
# Get the global variable dictionary
g = globals()
print(f"Number of variables: {len(g)}")
# View a specific variable
print(f"global_var: {g.get('global_var')}")
print(f"math: {g.get('math')}")
print(f"os: {g.get('os')}")
# Check if the variable exists
print('global_var' in g) # Output: True
print('unknown' in g) # Output: False
global_var = 100
global_list = [1, 2, 3]
import math
import os
# Get the global variable dictionary
g = globals()
print(f"Number of variables: {len(g)}")
# View a specific variable
print(f"global_var: {g.get('global_var')}")
print(f"math: {g.get('math')}")
print(f"os: {g.get('os')}")
# Check if the variable exists
print('global_var' in g) # Output: True
print('unknown' in g) # Output: False
Expected Output:
变量数量: ... global_var: 100 math: <module 'math'> os: <module 'os'> True False
Code Analysis:
- globals() returns all global variables of the current module.
- Includes imported modules, functions, classes, etc.
Example 2: Dynamically Operate Global Variables
Example
# Dynamically create global variables
globals()['dynamic_var'] = "Hello"
print(dynamic_var) # Output: Hello
# Batch create variables
for i in range(3):
globals()[f'var_{i}'] = i * 10
print(var_0, var_1, var_2) # Output: 0 10 20
# Use globals() in a function
def test():
g = globals()
g['x'] = 999
print(f"In function: x = {x}")
test()
print(f"Outside function: x = {x}") # Output: x = 999
globals()['dynamic_var'] = "Hello"
print(dynamic_var) # Output: Hello
# Batch create variables
for i in range(3):
globals()[f'var_{i}'] = i * 10
print(var_0, var_1, var_2) # Output: 0 10 20
# Use globals() in a function
def test():
g = globals()
g['x'] = 999
print(f"In function: x = {x}")
test()
print(f"Outside function: x = {x}") # Output: x = 999
Expected Output:
Hello 0 10 20 在函数中: x = 999 在函数外: x = 999
You can dynamically modify global variables, but this is generally not recommended.
globals()Mainly used for debugging and dynamic programming.
Other Extensions