$(...)
From Scriptwiki
This identifier allows you to create a dynamic match parameter in an event.
$(...)
You can use $1- to reference the incoming line.
Example
On *:TEXT:$(* $+ $me $+ *):#: { echo -a $nick just mentioned your nickname in $chan $+ . }
This example will echo to your active window whenever someone mentioned your nickname.
Note
You must use $(...) in the match text event for all other identifiers to be evaluated.
Correct: on *:text:$(hello $me):#: { ... } Incorrect: on *:text:hello $($me) *:#: { ... }