On Wed, 25 Aug 2010 01:44:22 am Evert Rol wrote:
> Why are you returning -1 here?
> -1 is a valid list index.
So? str.find() does the same thing. It guarantees to only return 0 or
positive indexes if it finds the substring, and only returns -1 to
indicate not found.
--
Steven D'Aprano
__
>>> I found it.
>>
>> Good.
>> Few generic comments nonetheless, just for the fun of it ;-).
>>
>>> This one does the trick :
>>>
>>> def find(strng, ch, start, step=1):
>>> index=start
>>> while 0 <= index < len(strng):
>>> if strng[index] == ch:
>>> return index
>>> index += step
>>> return -
> I found it.
Good.
Few generic comments nonetheless, just for the fun of it ;-).
> This one does the trick :
>
> def find(strng, ch, start, step=1):
> index=start
> while 0 <= index < len(strng):
> if strng[index] == ch:
> return index
> index += step
>
letter , "komt", aantal , "maal voor in het woord", fruit
Roelof
> Subject: Re: [Tutor] FW: find() problem
> From: evert@gmail.com
> Date: Tue, 24 Aug 2010 17:44:22 +0200
> CC: tutor@python.org
> To: rwob...@hotmail.com
>
> > > > > > d
> > > > > def find(strng, ch, start, step=1):
> > > > > index = start
> > > > The problem lies here, if you do a print on index, it never gets past
> > > > the first index of the number, so
> > > > your while loop below goes into an infinite loop.
> > > >
> > > > For example:
> > > > find('starfru
> Subject: Re: [Tutor] FW: find() problem
> From: evert@gmail.com
> Date: Tue, 24 Aug 2010 17:03:07 +0200
> CC: tutor@python.org
> To: rwob...@hotmail.com
>
> > > > def find(strng, ch, start, step=1):
> > > > index = start
> > > The prob
> > > def find(strng, ch, start, step=1):
> > > index = start
> > The problem lies here, if you do a print on index, it never gets past
> > the first index of the number, so
> > your while loop below goes into an infinite loop.
> >
> > For example:
> > find('starfruit','t',0) <- First time wil
