Regular Expressions in Triggers

[ddrager]

I have a template that has a lot of items, for example:

D8212G-MBBBB::bcms1-cb1-current.0
D8212G-MBBBB::bcms1-cb12-current.0
D8212G-MBBBB::bcms2-cb30-current.0
etc

I created a global regular expression:

.+bcms.-cb..?-current.0

With name pducircuits. Tested that it matches the strings above.

As a trigger, tried to set up:

{Template_PDU:regexp(@pducircuits).last(0)}>22

Also attempted to use:

{Template_PDU:@pducircuits.last(0)}>22

(I wasn't clear from the documentation the correct way to use regexs).

What is the correct way to use regular expressions in a trigger name, or am I going about this the wrong way?