DeprecationWarning: invalid escape sequence - what to use instead of \d?

python regex python-3.x
mchfrnc picture mchfrnc · May 24, 2018 · Viewed 52.7k times · Source

I've met a problem with re module in Python 3.6.5. I have this pattern in my regular expression:

'\\nRevision: (\d+)\\n'

But when I run it, I'm getting a DeprecationWarning.

I searched for the problem on SO, and haven't found the answer, actually - what should I use instead of \d+? Just [0-9]+ or maybe something else?

Answer

ACascarino picture ACascarino · May 24, 2018

Python 3 interprets string literals as Unicode strings, and therefore your \d is treated as an escaped Unicode character.

Declare your RegEx pattern as a raw string instead by prepending r, as below:

r'\nRevision: (\d+)\n'

This also means you can drop the escapes for \n as well since these will just be parsed as newline characters by re.

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