THE XML REVOLUTION - TECHNOLOGIES FOR THE FUTURE WEB

Axes

Available axes:

child the children of the context node
descendant all descendants (children, childrens children, ...)
parent the parent (empty if at the root)
ancestor all ancestors from the parent to the root
following-sibling siblings to the right
preceding-sibling siblings to the left
following all following nodes in the document, excluding descendants
preceding all preceding nodes in the document, excluding ancestors
attribute the attributes of the context node
namespace namespace declarations in the context node
self the context node itself
descendant-or-self the union of descendant and self
ancestor-or-self the union of ancestor and self

Note that attributes and namespace declarations are considered a special kind of nodes here.

Some of these axes assume a document ordering of the tree nodes. The ordering is the left-to-right preorder traversal of the document tree - which is the same as the order in the textual representation.

The resulting sets are ordered intuitively, either forward (in document order) or reverse (reverse document order).
For instance, following is a forward axis, and ancestor is a reverse axis.

(Frustratingly, each technology uses a slightly different tree model...)

`child`		the children of the context node
`descendant`		all descendants (children, childrens children, ...)
`parent`		the parent (empty if at the root)
`ancestor`		all ancestors from the parent to the root
`following-sibling`		siblings to the right
`preceding-sibling`		siblings to the left
`following`		all following nodes in the document, excluding descendants
`preceding`		all preceding nodes in the document, excluding ancestors
`attribute`		the attributes of the context node
`namespace`		namespace declarations in the context node
`self`		the context node itself
`descendant-or-self`		the union of `descendant` and `self`
`ancestor-or-self`		the union of `ancestor` and `self`