Xpath

Defines a named index for efficiently selecting nodes using the key() function in XSLT 1.0 and later.

Emits a diagnostic message to the processor's error output; optionally terminates transformation with terminate='yes'.

Maps a namespace prefix used in the stylesheet to a different prefix in the result tree, enabling stylesheets that generate XSLT.

Formats a number or automatically generates a sequence number based on the node's position in the document.

Asserts that the sequence contains zero or one items; raises a dynamic error if it contains more than one item.

Returns the absolute value of a numeric argument, removing any negative sign while preserving the numeric type.

Calls a function item with arguments supplied as an array, enabling dynamic dispatch with a variable argument list.

Returns a new array with an additional member appended at the end.

Returns the member of an array at a specified 1-based position.

Returns the first member of an array; raises an error if the array is empty.