While loop

Andre Engels andreengels at gmail.com
Thu Mar 5 13:54:15 EST 2009


On Thu, Mar 5, 2009 at 6:49 PM, Fab86 <fabien.hall at gmail.com> wrote:
> On Mar 5, 5:23 pm, Marco Mariani <ma... at sferacarta.com> wrote:
>> Fab86 wrote:
>> > Is it possible to get the program to catch the exception, wait 10
>> > seconds, then carry of from where it was rather than starting again?
>>
>> something like this? probably works in PASCAL as well :)
>>
>> > i=0
>> > while i < len(stuff):
>> >    try:
>> >       do_with(stuff[i])
>> >    except SomeError:
>> >       sleep(10)
>> >       continue
>> >    i+=1
>>
>>
>
> using sleep and then continue just makes the search start from the
> first search term like before.. Would it be easier to understand if I
> posted sections of my code?
>
> i = 0
> k = open('blah', 'w')
> domains = ["au", "ca", "nl", "be", "...]
> srch = WebSearch(app_id=YahooKey)
>
> while i<200:
>    try:
>        for domain in domains:
>            srch.query = "test site:.%s" % domain
>            res = srch.parse_results()
>            print >> k, res.total_results_available
>            i = i + 1
>
>    except SearchError:
>
> (I currently close then reopen document here then restart i to 0)
>
> Any ideas?

What you did not tell us was the inside loop. Just put code like
Tino's inside this inner loop:


while i<200:
   for domain in domains:
       srch.query = "test site:.%s" % domain
       while true:
           try:
                res = srch.parse_results()
                break
           except SearchError:
                time.sleep(10)
       print >> k, res.total_results_available
       i = i + 1


Or, if you want to to retry a maximum number of times:


max_retries = 50
while i<200:
   for domain in domains:
       srch.query = "test site:.%s" % domain
       retries = 0
       while true:
           try:
                res = srch.parse_results()
                break
           except SearchError:
                if retries < max_retries:
                    time.sleep(10)
                    retries += 1
                else:
                    raise TooManyRetriesError
       print >> k, res.total_results_available
       i = i + 1


-- 
André Engels, andreengels at gmail.com



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