I agree that this is inconsistent and confusing (and I'm quite curious how the implementation ended up this way).

But I have literally NEVER been bitten by this -- perhaps it's because I WAS bitten by it way back when, and then started the habit of ignoring empty strings before I split() -- I have a lot of code like:

line = line.strip()
if line:
   # do the splitting, or whatever ....

But as Eric says -- it is way too late to change this now -- at least the default behavior.


On Tue, Oct 20, 2020 at 9:08 AM Eric V. Smith <> wrote:
On 10/20/2020 11:52 AM, Antal Gábor wrote:
> Hey there,
> This is my first letter here, I'll try my best to explain the problem.
> First of all, I ran into this "problem" several times. I find
> str.split() a bit confusing. First of all, this is a corner case, but
> can happen like every day.
> print("".split())  # returns []
> print("".split(" "))  # returns ['']
> print("".split("\t"))  # returns ['']
> print("".split("\n"))  # returns ['']
> print("".splitlines())  # returns []
> So using split with or without a separator matters a lot, even when we
> use the same whitespace character split() uses. I think it is quite
> annoying. My idea is to return a list with an empty string in all
> cases mentioned above.
With probably millions (at least!) of uses of str.split in real code,
there's no way we can change this behavior.

You might be able to argue for an additional parameter to control this,
but I personally think the chances of confusion are too high. What I
usually do is write a wrapper for str.split if I don't like how it's


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Christopher Barker, PhD

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