On Sun, Sep 16, 2012 at 7:51 PM, Don Jennings <dfjenni...@gmail.com> wrote:
> This behavior seems strange to me: the find method of a string returns the
> position zero when you search for an empty string (granted, I can't quite
> figure out why you'd search for an empty string, either).
>
>>>> 'abc'.find('')
> 0
>
> Anyone care to share a good explantion for this behavior and possible use
> cases? Thanks!
It actually returns the value of "start":
>>> 'abc'.find('', 0)
0
>>> 'abc'.find('', 1)
1
>>> 'abc'.find('', 2)
2
It's looking for the length 0 substring ''. So it will match a 0
length slice at the given start position:
>>> 'abc'[0:0]
''
>>> 'abc'[1:1]
''
>>> 'abc'[2:2]
''
When you find 'b', for example, it searches for a length 1 slice:
>>> 'abc'.find('b')
1
>>> 'abc'[1:2]
'b'
The 'in' operator also searches for a substring:
>>> '' in 'abc'
True
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