This option specifies a function to be used to perform tag searches. The function gets the tag pattern and should return a List of matching tags. See tag-function for an explanation of how to write the function and an example. The value can be the name of a function, a lambda or a Funcref. See option-value-function for more information. This option cannot be set from a modeline or in the sandbox, for security reasons.

(default: empty)

not available when compiled without the +eval feature