[Tutor] Exception Handling

[bob gailer]

David wrote:
> David wrote:
>> Hi,
>> Is this the correct way to handle a ValueError exception and should I 
>> get in the practice of catching them? 

Well yes and no.

I think it is better to use the string method isdigit to test for digits 
only.

Also IMHO it is bad design to put a lot of code inside a try block. In 
this case the user might make a mistake on day and then is forced to 
reenter the year and month!

Better to write a function for requesting an integer from the user which 
loops until the user gets it right (with some way to escape if he gets 
frustrated and just wants to quit.

>> Also any suggestions on the program.
>> thanks
>> -david
>>
> Might help if I included the program :)
>
> #!/usr/bin/python
> import time
>
> print "Enter year as 0000"
> print "Enter month and day as 00"
>
> while True:
>     try:
>         yr = int(raw_input("What year were you born? "))
>         mn = int(raw_input("What month were you born? "))
>         dy = int(raw_input("What day were you born? "))
>         curr_date = time.strftime("%Y %m %d", time.gmtime())
>
>         ynum = int(time.strftime("%Y", time.gmtime())) - int(yr)
>         mnum = int(time.strftime("%m", time.gmtime()))
>         dnum = int(time.strftime("%d", time.gmtime()))
>         mn = int(mn)
>         dy = int(dy)
>
>         if mn - mnum:
>             print "You are %i" % ynum, "years old."
>             break
>         elif mn == mnum and dy < dnum:
>             print "You are %i" % ynum, "years old."
>             break
>         else:
>             ret = int(ynum) - 1
>             print "You are %i" % ret, "years old."
>             break
>     except ValueError:
>         print "Oops, You must enter a number!"
>
>
>


-- 
Bob Gailer
Chapel Hill NC 
919-636-4239