\p{L} any letter
\p{N} any number
\p{P} any punctuation
\p{Z} any whitespace

you can negate a character set with ^ inside the {} such as

\p{^L} any non-letter

So the equivalent to \w should be [\p{L}\p{N}] or any letter or any number

So that lets us handle any part of the expression except the \b, the word break. I’m not sure what the equivalent is here.

Note, I have no experience with the \p stuff myself, and I don’t know how it would actually play out or how close you could come to getting it to work. This is just a starting point

Thanks for this tip. Now for a Danish customer I need a regular expression that also include the Danish charaters æ, ø and å. And for this particular customer also the swedish character ö.

If I use this one: ^([\+*"*\s*,*'*\-*]*\w+\b\s*[\+*"*\s*,*'*\-*]*){3}$

these characters are not included.

If I use this one: ^(\W*\w+\b\W*){3}$

these characters are included, but they seem to count as spaces so that for example the word “hængelÃ¥s” (Danish word for padlock) is listed as a three word phrase.

Let me know if you have a solution for this - it will help me a lot!

Thanks,
Michael Dalmer

Cheers!

If I had guessed at the results before running this, my guesses would have been way off. I would have figured that our peak would have been at about 4 keyword phrases and more heavily weighted towards longer (brand and model specific) terms.

Thanks,
Loren

I believe that is possible to take into account. I never tried since in my case it was not very important. Try the following RegEx and let me know if it works for you. It accounts for both a - and a ‘ in the word:

^(\W*[\w-']+((?!['-]?\w)\b)\W*){4}$

It uses a Negative Lookahead and says “only match a boundary if [-']?\w does NOT match after it”.
The [-'] means match a - or a ‘ [-']? says match it if it’s there but it’s optional.

So for “John’s mini-bike” it hits a \b after the first n, but checks what is in front. it’s an ‘ followed by a \w, so it’s not allowed to match the \b. then it comes to another \b after the ‘, checks what is in front of it, and finds a \w. since the [-'] is optional thanks to the [-']? it still matches, preventing the \b from matching the word boundary. Then it sees a \b after the s. It looks ahead and finds a space. The Lookahead part does not match that, and the [w-'] CAN’T match it, so the \b matches it, and we go to the next repetition.

I plan to cover another really great use of the Negative Lookahead in another post.

By the way, there are also Lookbehinds … but GA does not support them as far as I can tell.

If that doesn’t seem to work, or if someone has a better way, I’d love to hear it.

BEWARE: don’t copy and paste it from these comments, since wordpress will probably convert the apostrophe into a curley single quote. Just type it into Notepad by hand, and use that.

^(\W*\w+\b\W*){3}$
Hmm. Yes agreed. Good point!
Tho I suspect you could/should ditch the \b pre the \W* then.
\W* … *should* pick that up anyway. (After shifting dirt all day long, I’m too tired and sore to swing round in my chair and read my regex book. )

Ahhh! Of course! Better:
^(\W*\w+\b){3}\W*$

???

It might even be worthwhile having a really good detailed look at the data coming in - you *may* be able to pull the lead \W* outside the braces after the caret:
^\W*(\w+\b){3}\W*$

Which is preferable from an efficiency perspective.
Though this will break (ie ignore) on the use of single quotes eg the example I gave previously.

Make sense?

Cheers!
- Steve

I did not realize that you didn’t have to escape inside []. And great examples of shortening up my unwieldy expressions, I didn’t even think to use \W !! However they don’t quite work. For example, ^(\W*\w+\b){3} will find a match with: “one two three four” so you need the $ anchor at the end. And once you put the $ anchor, you need to have your non-word characters on the right side too, to catch stuff after the last word. So what we probably need is something like ^(\W*\w+\b\W*){3}$ instead of ^(\W*\w+\b){3}.

BTW, and because Robbin would be disappointed if I didn’t.

^([\b-"+',]*\w+\b){3}

Is a simpler variant. Even that’s wrong tho, as it matches things like:
“crohn’s disease”
To pick the obvious example from GA on work’s site.

This works as the {3} … simply … acts like a multiplier. ie:
^([\b-"+',]*\w+\b)([\b-"+',]*\w+\b)([\b-"+',]*\w+\b)

But wait. There’s more! You can simplify even further.
^(\W*\w+\b){3}

Where \W == [^\w] in essence.
Still haven’t solved for “crohn’s disease”, but it’s 6.30am and I’ve not had coffee yet.

The \b is needed - as it can match the $ and hence why I’ve removed same, but also the “wrap” from the {3}, with the next \W*, you can match zero characters, so you can get \w+\w+\w+, which is NOT what is wanted. Always be careful of the asterix, it can easily break things by simply not matching anything - the zero case.

FWIW. Using the negated match as a pre/post-pender is a very obvious way to more or less match… everything. You don’t end up with any subtle cases that drop off.

Also, you don’t need to escape all characters inside []. Or put multipliers (eg *) against them. Your [] construct:
[\+*”*\s*,*’*\-*]
is equivalent to:
[+\s"-',*]
ie. You’ve included the ‘*’ as a character to match. Possibly not what was desired?

Generally it’s Bad Practice to escape characters that don’t need it. People start expecting special meanings where none exist and that’s not a good idea for the person coming after you. If/But/Maybe circumstances? Certainly!

Cheers! And thanks again for a great heads up!
- Steve

PS \w is *usually* equivalent to [a-zA-Z0-9_] Yup, Includes an underscore. Be Ware of your assumptions!