Differences between `input` and `raw_input` [dupli

Question

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• What's the difference between raw_input() and input() in python3.x? 6 answers

In a tutorial, I read that that there is a difference between input and raw_input. I discovered that they changed the behavior of these functions in the Python 3.0. What is the new behavior?

And why in the python console interpreter this

x = input()

Sends an error but if I put it in a file.py and run it, it does not?

Answer 1

In python 2.x, raw_input() returns a string and input() evaluates the input in the execution context in which it is called

>>> x = input()
"hello"
>>> y = input()
x + " world"
>>> y
'hello world'

In python 3.x, input has been scrapped and the function previously known as raw_input is now input. So you have to manually call compile and than eval if you want the old functionality.

python2.x                    python3.x

raw_input()   --------------> input()               
input()  -------------------> eval(input())     

In 3.x, the above session goes like this

>>> x = eval(input())
'hello'
>>> y = eval(input())
x + ' world'
>>> y
'hello world'
>>> 

So you were probably getting an error at the interpretor because you weren't putting quotes around your input. This is necessary because it's evaluated. Where you getting a name error?

Answer 2

Its simple:

1. raw_input() returns string values
2. while input() return integer values

For Example:

1.

x = raw_input("Enter some value = ")
print x

Output:

Enter some value = 123
'123'

2.

y = input("Enter some value = ") 
print y

Output:

Enter some value = 123
123

Hence if we perform x + x = It will output as 123123

while if we perform y + y = It will output as 246

Answer 3

input() vs raw_input()

raw_input collects the characters the user types and presents them as a string. input() doesn't just evaluate numbers but rather treats any input as Python code and tries to execute it. Knowledgeable but malicious user could type in a Python command that can even deleted a file. Stick to raw_input() and convert the string into the data type you need using Python's built in conversion functions.

Also input(), is not safe from user errors! It expects a valid Python expression as input; if the input is not syntactically valid, a SyntaxError will be raised.