element is

operator

Return type:: Switch
Returns:: Returns true if the element is the specified element, and false otherwise. Replacing is with isnt reverses the result.

Syntax

element (of element-expression)? (is | isnt) namespace-modifier? (element-name | element-name-list)

Purpose

element is tests whether the current element of the currently-active parse is 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-expression is not specified, the test applies to the current element. If element-expression is specified, the test applies to the element specified by element-expression.

You can specify an element name dynamically by using the identity operator (~) followed by a string expression, for example:

  define string function
     f ()
  elsewhere
  
  
  element #implied when element is ~f ()
     suppress

Related Syntax