not function

The fn:not function returns false if the effective boolean value of a sequence is true and returns true if the effective boolean value of a sequence is false.

Syntax

Read syntax diagramSkip visual syntax diagramfn:not( sequence-expression)
sequence-expression
Any sequence that contains items of any type, or the empty sequence.

Returned value

If sequence-expression is not an empty sequence, then the value that is returned is true if the effective Boolean value of the sequence is false. The returned value is false if the effective boolean value of the sequence is true.

If sequence-expression is the empty sequence, the returned value is true.

Example

The following function returns false because the effective Boolean value of a node is true.
fn:not(<employee />)