Apple Numbers Reg.Extract function not returning first word (using boundary assertion with Positive lookahead)

I copied the expression from a book as follows. Space appears as if it’s there. I probably should advise author to correct typo.

on the other hand, there’s learning curve to define Regex carefully; seems not very tolerant of line containing space(s) between words.

thanks for free advice!

Something like this won't care if in the source string you have and extra space before the dot or not.

=REGEX.EXTRACT(A3,"[\b ]([\w ]+)(?=\.)",1,1)

The [\b ] matches a boundary or a space.

The ([\w ]+) is a capture group for word characters or spaces.

The first 1 means first match.

The second 1 means first capture group.

SG

Your formula works perfectly fine as it is. The source string is the problem. It has a space of some kind between the 123 and the first dot. If you are expecting the result to be "123", that part of the string does not match your criteria.

Working here. You've forgotten the " " around your regular expression in the formula.

=REGEX.EXTRACT(A3,"\b\w+\b(?=\.)",1)

SG

SunnyInToronto wrote:

“\b\w+(?=\.)”

is shorter

It's shorter. But it does work if you've got an extra space in the source string.

The longer version handles that situation.

SG

This also works for both cells:

(REGEX.EXTRACT(A2,"(?<=\w)\s?(\d)\s?(?=.xpto)",1,1)