Extension of Python's eval

Question

string = "if X > 3 :\n   print(\"X is Greater\")\nelse :\n   print(\"X is Lesser\")"

""" It prints the string as an indented code of if else statements if X is greater than 3
X is greater else it prints X is lesser"""

X = 6

eval(string)

Can eval() in python be used in this way or is there anything I'm missing .

Bhargav Rao · Accepted Answer · 2015-06-10T17:35:00.070

3

eval is used only for expressions. From the documentation

The expression argument is parsed and evaluated as a Python expression

Use exec here

>>> string = "if X > 3 :\n   print(\"X is Greater\")\nelse :\n   print(\"X is Lesser\")"
>>> X = 6
>>> exec(string)
X is Greater

However do note that both the statements are quite risky to use. (See eval really is dangerous)

edited Jun 10 '15 at 17:35

answered Jun 10 '15 at 17:33

Bhargav Rao

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really you should avoid both like the plague if you can ... :P but yeah +1 – Joran Beasley Jun 10 '15 at 17:34
Hehe. Yeah. I was writing about that – Bhargav Rao Jun 10 '15 at 17:35

Extension of Python's eval

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