looping question 4 NEWB

[manstey]

Thanks Marc, that was very helpful.

Marc 'BlackJack' Rintsch wrote:
> In <1152182594.168085.10660 at m73g2000cwd.googlegroups.com>, manstey wrote:
>
> > I often have code like this:
> >
> > data='asdfbasdf'
> > find = (('a','f')('s','g'),('x','y'))
> > for i in find:
> >    if i[0] in data:
> >        data = data.replace(i[0],i[1])
> >
> > is there a faster way of implementing this? Also, does the if clause
> > increase the speed?
>
> It decreases it.  You search through `data` in the ``if`` clause.  If it's
> `False` then you have searched the whole data and skip the replace.  If
> it's `True` you searched into data until there's a match and the the
> `replace()` starts again from the start and searches/replaces through the
> whole data.
>
> You can get rid of the indexes and make the code a bit clearer by the way:
>
> for old, new in find:
>     data = data.replace(old, new)
> 
> Ciao,
> 	Marc 'BlackJack' Rintsch