Python regex: Including whitespace inside character range

Question

I have a regular expression that matches alphabets, numbers, _ and - (with a minimum and maximum length).

^[a-zA-Z0-9_-]{3,100}$

I want to include whitespace in that set of characters.

According to the Python documentation:

Character classes such as \w or \S are also accepted inside a set.

So I tried:

^[a-zA-Z0-9_-\s]{3,100}$

But it gives bad character range error. How can I include whitespace in the above set?

score 25 · Accepted Answer · answered Oct 30 '12 at 15:34

25

The problem is not the \s but the - which indicates a character range, unless it is at the end or start of the class. Use this:

^[a-zA-Z0-9_\s-]{3,100}$

answered Oct 30 '12 at 15:34

Martin Ender

Thanks m.buettner. Position of - was the problem – Nitish Parkar Oct 30 '12 at 15:48

score 3 · Answer 2 · answered Oct 30 '12 at 15:36

3

^[-a-zA-Z0-9_\s]{3,100}

_-\s was interpreted as a range. A dash representing itself has to be the first or last character inside [...]

answered Oct 30 '12 at 15:36

dda

Thanks dda. The problem was indeed the position of - – Nitish Parkar Oct 30 '12 at 15:50

score -1 · Answer 3 · answered May 27 '16 at 02:29

-1

You're on the right track, Add a second backslash to escape the slash, because the backslash is an escape character.

^[a-zA-Z0-9_\\-\\s]{3,100}$

answered May 27 '16 at 02:29

David Lai

1

Sorry for the downvote, @david-lai. I think this answer is inaccurate in that it doesn't solve the problem; despite working around the reported error. It might be better to remove your answer, imo. – Eric McLachlan Jan 08 '20 at 09:15

3 Answers3