[Tutor] Exeption errors

[Lloyd Kvam]

One quibble.  It is best to limit the try block to exactly what we mean
to be testing.  I'd recommend changing the code to look like this.

while True:
    x=raw_input("Enter a number: ")
    try:
         x=int(x)
    # put the except immediately after what we mean to try
    except ValueError:
         print "that is not a number"
    # put the rest of the "normal processing" in a try/else block
    else:
         if x==1:
             break

         print "Thats not 1"

On Sat, 2004-08-21 at 14:00, Kent Johnson wrote:
> Kevin,
> 
> You have to get the try block into the loop, so the loop will continue 
> after an exception is raised. This is a little tricky because the loop 
> condition (int(x) != 1) itself is raising the exception.
> 
> One solution is to use an infinite loop with a break condition, like this:
> while True:
>      x=raw_input("Enter a number: ")
>      try:
>          x=int(x)
>          if x==1:
>              break
> 
>          print "Thats not 1"
>      except ValueError:
>          print "that is not a number"
> 
> I prefer this form of the loop anyway because it doesn't duplicate the 
> input code. In general instead of this:
> x = doSomething()
> while not someCondition(x):
>    x = doSomething()
> 
> I prefer this:
> while True:
>    x = doSomething()
>    if someCondition(x):
>      break
> 
> Kent
> 
> At 01:23 PM 8/21/2004 -0400, Kevin wrote:
> >I am playing around with Exeption Errors this is the code I did:
> >x=raw_input("Enter a number: ")
> >try:
> >     while int(x) != 1:
> >         print "Thats not 1"
> >         x=raw_input("Enter a number: ")
> >except ValueError:
> >         print "that is not a number"
> >
> >it works to a point when I type in a number that is not a one it will keep 
> >saying Thats not 1, but when I put in a letter it will say that is not a 
> >number and then exit the program. How do I make it look again?
> >
> >Thanks
> >Kevin
> >
> >
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-- 

Lloyd Kvam
Venix Corp.
1 Court Street, Suite 378
Lebanon, NH 03766-1358

voice:	603-653-8139
fax:	801-459-9582
-- 

Lloyd Kvam
Venix Corp.
1 Court Street, Suite 378
Lebanon, NH 03766-1358

voice:	603-653-8139
fax:	801-459-9582