<<.from-version "5.1.20">>The conditional filter operators allow ''if-then-else'' logic to be expressed within filters.
The foundation is the convention that an empty list can be used to represent the boolean value ''false'' and a list with at one (or more) entries to represent ''true''.
The conditional operators are:
* [[then Operator]] replaces any input values with a constant string. For example:
<<.inline-operator-example "[[New Tiddler]is[missing]then[I am missing]else[No I am not missing]]">>
The [[else Operator]] can be used to apply a defaults for missing values. In this example, we take advantage of the fact that the [[get Operator]] returns an empty list if the field or tiddler does not exist: