Frankenstring

[Andreas Lobinger]

Aloha,

Thomas Lotze wrote:
>>A string, and a pointer on that string. If you give up the boundary
>>condition to tell backwards, you can start to eat up the string via f =
>>f[p:]. There was a performance difference with that, in fact it was faster
>>~4% on a python2.2.

> When I tried it just now, it was the other way around. Eating up the
> string was slower, which makes sense to me since it involves creating new
> string objects all the time.

I expected the f[p:] also to be slower, the 4% i only measured on one 
platform. Most propably the CG and memory management isn't the same.

>>I dont't expect any iterator solution to be faster than that.

> It's not so much an issue of iterators, but handling Python objects
> for every char. Iterators would actually be quite helpful for searching: I
> wonder why there doesn't seem to be an str.iterfind or str.itersplit
> thing. And I wonder whether there shouldn't be str.findany and
> str.iterfindany, which takes a sequence as an argument and returns the
> next match on any element of it.

There is a finditer in the re. I'm currently rewriting a few pattern
matching things and find it quite valueable.

 >>> import re
 >>> pat = re.compile('[57]')
 >>> f = "754356184756046104564"
 >>> for a in pat.finditer(f):
...  print a.start(),f[a.start()]
...
0 7
1 5
4 5
9 7
10 5
18 5

Wishing a happy day
		LOBI