It would be awesome to have some sort of validation for {<macro>.<func>(<params>)} macro in a trigger name.

Examples (trigger name with an issue: e.g. missing closing bracket or there is not escaped character):

Result: {{ITEM.VALUE}.regsub(([0-9]),\1)}

Result: {{ITEM.VALUE}.regsub("("[0-9]")",\1)}

Result: {{ITEM.VALUE}.regsub("([0-9])",\1)

Result will look like this:

Result: {test number is 5.regsub("([0-9])",\1)

imagine if you are using this macro for the log file or SNMP traps monitoring. Zabbix will display "as is" log records or traps in the problem name (see 2017.55.44.png screenshot) instead of extracted value ("2017.59.23.png").