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Date: Mon, 3 Jun 2013 12:08:07 +1000
Subject: Re: Issue converting to string to integer.
From: Chris Angelico <rosuav@gmail.com>
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On Mon, Jun 3, 2013 at 11:52 AM, Dan Sommers <dan@tombstonezero.net> wrote:
> On Sun, 02 Jun 2013 18:12:33 -0700, Fdama wrote:
>
>> I combined the int conversion and the input on the same line, rather
>> than to have two different statements. But got an error message:
>
>> Traceback (most recent call last):
>>   File "C:\Users\Faisal\Documents\python\pizza_slicer.py", line 23, in <module>
>>     start=int(input("\nStart: "))
>> ValueError: invalid literal for int() with base 10: ''
>>
>> Could someone tell me why I got this error message?
>
> The difference is what used to happen in between the input and the
> conversion.  In the first version, the "if" statement prevents the
> conversion from happening when there is no input.  In the second
> version, though, python tries to do the conversion with no input, and
> fails.

You could combine them in, as long as you're okay with blank input and
input of '0' being folded to the same:

start = int(input("\nStart: ") or 0)

ChrisA