ANSIBLE - Handlers listen

Question

Really short question. I just wanted to know why when we use handlers the "listen" section doesn't take variable?

- name: notify components 
  command: echo "this task will notify all the components"
  notify: "hello world"

- debug:
    msg: "Hello world !!"
  listen: "hello world"

- set_fact:
    myvar: "hello world"
  listen: "hello world"

- debug:
    msg: "Hello world !! with var"
  listen: "{{myvar}}"

Why this section doesn't work? Listen doesn't take variables?

Answer 1

This is specifically documented in the notes on handlers documentation

Handler names are templatable and listen topics are not.