For loop and If condition- python

Question

I try to run this code and write "hello" but get en error:

Value = input("Type less than 6 characters: ")
LetterNum = 1
for Letter in Value: 
 print("Letter ", LetterNum, " is ", Letter)
 LetterNum+=1
 if LetterNum > 6:
 print("The string is too long!")
 break

get error:

>>> 
Type less than 6 characters: hello
Traceback (most recent call last):
 File "C:/Users/yaron.KAYAMOT/Desktop/forBreak.py", line 1, in <module>
 Value = input("Type less than 6 characters: ")
 File "<string>", line 1, in <module>
NameError: name 'hello' is not defined
>>> 

i don't know why it don't work

• jonrsharpe: In Python 2.x, use raw_input
• jonrsharpe: possible duplicate of "NameError: name '' is not defined" after user input in Python

Answer 1

TL;DR: use raw_input()

---

That is because input() in Python 2.7 tries to evaluate your input (literally: hello is interpreted the same way as it will be written in your code):

>>> input("Type less than 6 characters: ")
Type less than 6 characters: 'hello'
'hello'

The word hello is parsed as variable, so input() complains the same way interpreter will do:

>>> hello
...
NameError: name 'hello' is not defined
>>> input()
hello
...
NameError: name 'hello' is not defined
>>> hello = 1
>>> hello
1
>>> input()
hello
1

Use raw_input() instead which returns raw string:

>>> raw_input("Type less than 6 characters: ")
Type less than 6 characters: hello
'hello'

This design flaw was fixed in Python 3.

Answer 2

You should use raw_input() instead of input().

according to document

input([prompt]) Equivalent to eval(raw_input(prompt)).

If input is some numbers,you may use 'input()'.But you should better never use 'input()',use 'int(raw_input())' instead.

Value = raw_input("Type less than 6 characters: ")
LetterNum = 1
for Letter in Value: 
 print("Letter ", LetterNum, " is ", Letter)
 LetterNum+=1
 if LetterNum > 6:
 print("The string is too long!")
 break
Type less than 7 characters: hello
('Letter ', 1, ' is ', 'h')
('Letter ', 2, ' is ', 'e')
('Letter ', 3, ' is ', 'l')
('Letter ', 4, ' is ', 'l')
('Letter ', 5, ' is ', 'o')

• jonrsharpe: "input() is for numbers" - not really. You should pretty much never use it.
• woodrat: It's my fault. my english is not very good. "input() is for numbers" is not precisely.