The documentation of the xml.dom module does not mention the CharacterData interface at all, although it is implemented and Text, Comment and CDATASection inherit from it. As a result the length attribute and the substringData(), appendData(), insertData(), deleteData() and replaceData() methods are not documented. data is documented separately for Text and for Comment.

Other members which are implemented, but are not documented:

• Node.ownerDocument, Node.isSupported(), Node.getUserData(), Node.setUserData()
• Document.doctype, Document.implementation, Document.documentURI, Document.strictErrorChecking
• Document.createDocumentFragment(), Document.createCDATASection(), Document.importNode(), Document.renameNode()
• Element.setIdAttribute(), Element.setIdAttributeNS(), Element.setIdAttributeNode()
• Attr.isId, Attr.ownerElement
• Text.wholeText, Text.splitText(), Text.replaceWholeText()

Linked PRs

• gh-151943: Document the CharacterData interface and other DOM members #155632