I'm not quite sure whats happening: with the hardcoded boundaries ^((?:[/dp/]|$)([A-Z0-9]{10}))$, the tests fail and without them (?:[/dp/]|$)([A-Z0-9]{10}) they pass. I'm looking into it more, but if you have any quick insights, I'd appreciate the feedback.

Thanks!

This is happening because with hardcoded boundaries the whole match needs to be in one line with nothing else around it.

http://www.amazon.com/Kindle-Wireless-Reading-Display-Generation/dp/B0015T963C

Your regex is matching to only /dp/B0015T963C, so it doesn't match as there is something before it. If you add only this part as a test it will pass. 😄

This is happening because with hardcoded boundaries the whole match needs to be in one line with nothing else around it.

http://www.amazon.com/Kindle-Wireless-Reading-Display-Generation/dp/B0015T963C

Your regex is matching to only /dp/B0015T963C, so it doesn't match as there is something before it. If you add only this part as a test it will pass. smile

Oh, I see! I had lost sight of main use of pyWhat while using regex101 and was extracting ASINs from strings instead of checking if a string is an ASIN. Updating now with new regex removing URL specific aspects.

This is happening because with hardcoded boundaries the whole match needs to be in one line with nothing else around it.
http://www.amazon.com/Kindle-Wireless-Reading-Display-Generation/dp/B0015T963C
Your regex is matching to only /dp/B0015T963C, so it doesn't match as there is something before it. If you add only this part as a test it will pass. smile

Oh, I see! I had lost sight of main use of pyWhat while using regex101 and was extracting ASINs from strings instead of checking if a string is an ASIN. Updating now with new regex removing URL specific aspects.

I think in bounardyless mode we do extract that string, but we need it to have boundaries in our database so we can take them away in our boundaryless mode :)