Is there a complete guide containing all regex characters and their meaning in Tealium?

[david_roose]

For example, the Google Analytics regex guide (Perl-based): https://support.google.com/analytics/answer/1034324?hl=en Optionally, it may be sufficient to state on which programming language it is based, as there are books available on this topic, for example: http://shop.oreilly.com/product/0636920023630.do

[craig_rouse · Accepted solution]

Hi David, Since Tealium is JavaScript based, it uses the JavaScript regex engine. Any regex you enter in the Tealium UI is parsed and converted into a standard JS regex before execution. Using the leading and trailing forward slashes is optional, unless you want to use a modifier such as "/g" or "/i". You can find a full JS regex reference here: http://www.regular-expressions.info/javascript.html Hope this helps. Craig.

[fiann_ohagan]

This is also a useful resource, which can show why your regular expression is (not) matching. http://regexponline.com/

[brian_greig]

One of my favorite resources is: https://regex101.com/#javascript . Great tool for testing your regex before implementing in production.

[ksugam]

I am reviving a very old thread but since its related to regex, I chose to mention here-

Has anybody faced utag.js errors on firefox and safari browsers due to negative lookbacks in regex. It caused an issue on one of my publishes as Chrome works perfectly fine.

I am trying to write a regex within a load rule to make sure the URL follows below pattern-

subdomain.abc.com (should match)

www.abc.com (should return false).

Hence I built a regex using regex101 as- 

[a-z]+(?<!www)\.abc\.com

This works fine for chrome but fails to compile on firefox and safari due to negative look back (?<). 

Can anybody help me with this

[michaelLearo]

Hi @ksugam,

Is it possible to use something like [a-z]+([^www])\.abc\.com to meet your needs?

Tested in FF:

var a = /[a-z]+([^www])\.abc\.com/;

a.match("www.abc.com") //false
a.match("somedomain.abc.com")//true

*Chrome is the only browser that supports lookbehinds from ECMA2018 from what I read.

[ksugam]

Thanks Michael. Works now on all browsers.