Abstract
Non-element Selectors extends [SELECTORS4] and allow selecting other kinds of document nodes than elements. This is useful when selectors are used as a general document query language.
Non-element Selectors are not intended to be used in CSS, but only as a separate query language in other host environments.
CSS is a language for describing the rendering of structured documents
(such as HTML and XML)
on screen, on paper, etc.
This specification is obsolete. Please see the latest CSS Snapshot for the specifications that make up CSS.
This section describes the status of this document at the time of
its publication. Other documents may supersede this document. A list of
current W3C publications and the latest revision of this technical report
can be found in the W3C technical reports
index at https://www.w3.org/TR/.
Publication as a Working Group Note does not imply endorsement by the
W3C Membership. This is a draft document and may be updated, replaced or
obsoleted by other documents at any time. It is inappropriate to cite this
document as other than work in progress.
GitHub Issues are preferred for discussion of this specification.
When filing an issue, please put the text “selectors-nonelement” in the title,
preferably like this:
“[selectors-nonelement] …summary of comment…”.
All issues and comments are archived,
and there is also a historical archive.
This document was produced by the CSS Working Group.
This document was produced by a group operating under the W3C Patent Policy.
This document is governed by the 1 March 2019 W3C Process Document.
1. Introduction
Selectors are a very popular mechanism for selecting things in HTML and XML content.
They are not used only in CSS [CSS3SYN] but also as a standalone query language in libraries like jQuery,
in newer standardized browser APIs like [SELECTORS-API] and in other Web standards like ITS 2.0.
The [SELECTORS4] specification only defines selectors for selecting element nodes from the document,
but some uses of Selectors would like to select other types of nodes as well.
This specification extends [SELECTORS4] with additional selectors
that can be used for selecting non-element nodes in a document tree.
Note: Currently the draft only defines means for selecting and matching attribute nodes,
but other kinds of nodes, such as comments or processing instructions, might be supported in the future.
2. Non-element Selectors
2.1. Attribute node selector
An attribute node selector represents an attribute node in a document tree.
Its syntax is:
::attr() = ::attr( ? )
= [ ? '|' ]?
= | '*'
= | '*'
No whitespace is allowed between the tokens of .
is divided into two halves:
an optional prefix preceding a '|' character,
and an attribute name following it.
If the is provided as an ,
it must match a declared namespace prefix,
in which case the selector only matches attributes in that namespace;
if it doesn’t match a declared namespace prefix,
the selector matches nothing.
If the is provided as a * character,
the selector matches attributes in any namespace.
If the is omitted,
the selector only matches attributes in no namespace.
If the is an ,
the selector matches attributes with that name.
If the is a * character,
the selector matches attributes with any name.
If the is omitted entirely,
the selector matches any attribute in any namespace.
The selector matches an attribute node with the given namespace and name on the originating element,
if such an attribute exists.
The selector uses pseudo-element syntax.
The following ITS rules use an attribute node selector
to switch off translatability of
title attribute on
abbr elements.
Although entirely valid in Selectors used in the scope of CSS, attribute node selectors never generate boxes.