Regex question about \d

[Gerhard Häring]

* Tim Peters <tim.one at comcast.net> [2002-04-07 14:59 -0400]:
> [Gerhard Häring]
> > Can somebody please explain this to me:
> >
> > >>> print re.search(r"\d*", "asdfsfafsw 453 dfsa").group(0)
> >
> > >>> print re.search(r"\d+", "asdfsfafsw 453 dfsa").group(0)
> > 453
> >
> > Why doesn't the first regex match the digits?
> 
> A Python/Perl regexp search matches at the leftmost position it can match.
> Any regexp of the form (whatever)* can match an empty string, so searching
> for any such regexp matches at the start of the string.  If the only thing
> it can match at the start of the string is the empty string, good enough:
> that is a match.

Ah! Ok.

Thanks,

Gerhard
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reduce(lambda x,y:x+y,map(lambda x:chr(ord(x)^42),tuple('zS^BED\nX_FOY\x0b')))