Create trigger to check if a value is in a item

[charlepr]

Hi,

I am trying to find a way to write a trigger which checks for a hostname which is available in the item

Problem:

item List_of_hosts = {sys1,sys2,sys3,sys4,sys5}

item host_name = {sys1}

Trigger should check value of host_name is in the item List_of_hosts