operator
true
if the element or one of its ancestors is the specified element, and false
otherwise. Replacing
is
with isnt
reverses the result.
open element element-qualifier? (is | isnt) namespace-modifier? (element-name | element-name-list)
open element is
tests whether the element stack of the currently-active parse contains an instance of the
element element-name, or one of the elements listed in element-name-list. element-name-list is a parenthesized list of elements, separated by |
. Replacing is
with isnt
will reverse these results.
If element-qualifier is not specified, the test searches the element stack starting with the current element. If element-qualifier is specified, the search begins with the element specified by element-qualifier.
You can specify the name dynamically by using the identity operator (~
) followed by a string
expression: for example,
define string function f () elsewhere element #implied when open element is ~f () suppress