Python: eval() function

Last update on August 19 2022 21:51:34 (UTC/GMT +8 hours)

eval() function

The eval() function is used to evaluate the specified expression. If the expression is a correct Python statement, it will be executed.

Version:

(Python 3)

Syntax:

eval(expression, globals=None, locals=None)

Parameter:

Name	Description	Required / Optional
expression	A string as parsed that will evaluated as a Python expression.	Required
globals	A dictionary	Optional
locals	A mapping object.	Optional

Example: Python eval() function

x = 5
print(eval('x+1'))
print(eval('x'))

Output:

6
5

Example: Passing empty dictionary as globals parameter

from math import *
print(eval('dir()', {}))

#Following code will raise an exception
print(eval('sqrt(36)', {}))

Output:

['__builtins__']
Traceback (most recent call last):
  File "/tmp/sessions/5cb89b87138fc37f/main.py", line 5, in 
    print(eval('sqrt(36)', {}))
  File "", line 1, in 
NameError: name 'sqrt' is not defined

Python Code Editor:

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