TypeError: list indices must be integers

[John Machin]

On Dec 31 2008, 3:26 pm, dubux <wx1... at gmail.com> wrote:
> thanks for help everyone. it turned out the function itself worked
> fine.. it was the way i was calling it that was messing everything up.
> i ended up re-doing the whole thing as follows, and it now works
> perfectly.
>
> def news(x,y):
>         news_file = '/home/scam/Desktop/www/info/news'
>         news = open(news_file, 'r')
>         news_list = news.readlines()
>         news.close()
>         if x == 'date':
>                 mylist = map(lambda i: news_list[i], filter(lambda i: i%2 == 0, range
> (len(news_list))))
>                 date = mylist[y].replace("\n","")
>                 return '<center><p>%s</p></center>\n\n' % (date)
>         if x == 'news':
>                 mylist = map(lambda i: news_list[i], filter(lambda i: i%2 == 1, range
> (len(news_list))))
>                 news = mylist[y].replace("\n","")
>                 return '<center><p>%s</p></center>\n<br>\n' % (news)
>         else:
>                 return news_list
>
> news_parse, count, news_list = " ", 0, news('list','list')
> newss = map(lambda i: news_list[i], filter(lambda i: i%2 == 1, range
> (len(news_list))))
> while count < len(newss):
>         get_date = news('date', count)
>         get_news = news('news', count)
>         news_parse = '%s %s %s' % (news_parse, get_date, get_news)
>         count = count + 1

Unless I'm sorely mistaken, the whole of the above can be replaced by
something like (untested):

news_file = '/home/scam/Desktop/www/info/news'
news = open(news_file, 'r')
accum = []
for lineno, line in enumerate(news):
    accum.append('<center><p>%s</p></center>\n%s\n' % (line.strip(),
('', '<br>')[lineno % 1]))
news_parse = ' '.join(accum)
news.close()
count = (lineno + 1) // 2 # if indeed count is needed

with the virtues of brevity and speed ... if there are N (date, news)
items, your code reads the file 2*N+1 times!!!

How big is N?