Changing the value of a for loop index on the fly

[Ron]

On Wed, 23 Mar 2005 23:27:54 +0100, "Gabriel F. Alcober"
<gfa1977 at yahoo.ca> wrote:

>Hi! There goes a newbie trouble:
>
>for i in range(0, len(subject)):
>        if subject[i] in preps:
>            psubject.append(noun_syn_parser(subject[0:i]))
>            subject[0:i] = []
>
>Since the last line eliminates some elements of the list, I'm wondering 
>if it's somehow possible to change the value of "i" to 0 in order not to 
>get an index error. Any other ideas?
>Thanks in advance.
>

I going to guess that you probably want something more like below.
The routine you have because of the deletions, the index and the
subjects list get way out of sync, which is why you get the index
error on 'subject[i]'.  

Try this which uses no indexes, it should be closer to what you want.

for subj in subjects:
    sub2.append(subj)
    if subj in preps:
        psubject.append(noun_sys_parser(subj2))
        subj2 = []