[Tutor] CGI Calculator

[Darren Williams]

Now another problem - the script is just printing the word 'Tokens' over and 
over again, it's supposed to work like this (JavaScript version made by 
me) - http://nazkyn.brinkster.net/1.8.html

Thanks in advance for any help :)

----- Original Message ----- 
From: "Eric Brunson" <brunson at brunson.com>
To: "Darren Williams" <D3IBZ at hotmail.com>
Cc: <tutor at python.org>
Sent: Monday, July 16, 2007 2:01 PM
Subject: Re: [Tutor] CGI Calculator


> Darren Williams wrote:
>> Ok, now i've modified my script but am getting another error, i've 
>> commented a few useless (hopefully) lines out -
>>
>> #!/usr/bin/env python
>>
>> import cgitb; cgitb.enable()
>> import cgi
>>
>>
> [snip]
>>         17     while usedPockets > totalJunkies - labSpace * 17:
>>
>>         18         Tokens = Tokens + 1
>>
>>         19         usedPockets = (usedPockets - totalJunkies + labSpace) 
>> * 17
>>
>>      usedPockets = '192000', totalJunkies = '200', labSpace = '0'
>>
>> TypeError: unsupported operand type(s) for -: 'str' and 'str'
>>      args = ("unsupported operand type(s) for -: 'str' and 'str'",)
>>
>
> What does "dog" - "cat" mean?  Similarly, what does "100" - "12" mean? 
> It's not the same in Python as 100 - 12, because those are numbers, "100" 
> and "12" are strings which happen to represent numbers.
>
> You need to coerce those strings into integers, maybe like this:
>
> usedPockets = int(form["usedPockets"].value)
>
> When you do that, you'll probably need to catch any exception that could 
> occur if the string can't be converted.
>
>>
>>
>> It's confused me - it says I can't subtract a string from a string but 
>> then gives the value's of the variables (that I randomly entered into the 
>> form) at the bottom - usedPockets = '192000', totalJunkies = '200', 
>> labSpace = '0'
>>
>
>