The function to determine if a key-value pair should be ignored. It should accept
a key and a value, and return true if the pair should be ignored, or false otherwise.
Default value is a function that always returns false.
(key, value): boolean
Parameters
key: string
value: any
Returns boolean
Returns number
The count of non-empty and non-ignored values in the filter data object.
Counts the number of non-empty and non-ignored values in the given filter data object.