book

XML in a Nutshell, 3rd Edition

by Elliotte Rusty Harold, W. Scott Means

September 2004

Intermediate to advanced

712 pages

24h 45m

English

O'Reilly Media, Inc.

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2.2.1.1. Empty elements2.2.1.2. Case-sensitivity
2.2.2.1. Parents and children2.2.2.2. The root element
3.1.2.1. Public IDs
3.3.1.1. CDATA3.3.1.2. NMTOKEN3.3.1.3. NMTOKENS3.3.1.4. Enumeration3.3.1.5. ID3.3.1.6. IDREF3.3.1.7. IDREFS3.3.1.8. ENTITY3.3.1.9. ENTITIES3.3.1.10. NOTATION
7.1.3.1. The XML declaration and processing instructions7.1.3.2. Empty elements7.1.3.3. Entity references7.1.3.4. Other unsupported features
7.2.1.1. The required href and type pseudo-attributes7.2.1.2. The media pseudo-attribute7.2.1.3. The charset pseudo-attribute7.2.1.4. The alternate and title pseudo-attributes
10.4.2.1. Multiple arcs from one arc element10.4.2.2. Arc titles10.4.2.3. Arc roles
16.1.2.1. XML as a part of the Web: REST16.1.2.2. XML for procedure calls over HTTP: XML-RPC16.1.2.3. XML envelopes and messages: SOAP16.1.2.4. Other options: BEEP and XMPP
16.2.1.1. Where and how will new documents be created?16.2.1.2. How complex will the document be?16.2.1.3. How will documents be consumed?16.2.1.4. How widely will the resulting documents be distributed?16.2.1.5. Will others need to incorporate this document structure into their own applications?
16.2.2.1. XML vocabulary development
16.2.5.1. Will instance documents need to be validated using a DTD?16.2.5.2. Will markup from this application need to be embedded in other applications?16.2.5.3. Are there legacy XML document formats to support?
17.2.2.1. The xs:documentation element17.2.2.2. The xs:appinfo element
17.2.3.1. Simple types
17.2.4.1. Attribute groups
17.6.2.1. Handling whitespace17.6.2.2. Restricting length17.6.2.3. Enumerations17.6.2.4. Numeric facets17.6.2.4.1. Minimum and maximum values17.6.2.4.2. Length and precision17.6.2.5. Enforcing format17.6.2.6. Lists17.6.2.7. Unions
17.8.1.1. Including external declarations17.8.1.2. Modifying external declarations17.8.1.3. Importing schemas for other namespaces
17.8.2.1. Deriving by extension17.8.2.2. Deriving by restriction17.8.2.3. Using derived types
17.9.4.1. Forcing uniqueness17.9.4.2. Keys and references
19.4.1.1. DocumentType19.4.1.2. ProcessingInstruction19.4.1.3. Notation19.4.1.4. Entity
19.4.2.1. Document19.4.2.2. DocumentFragment19.4.2.3. Element19.4.2.4. Attr19.4.2.5. CharacterData19.4.2.6. Comment19.4.2.7. EntityReference19.4.2.8. Text19.4.2.9. CDATASection
19.6.1.1. NameList19.6.1.2. DOMImplementationList19.6.1.3. DOMImplementationSource19.6.1.4. TypeInfo19.6.1.5. UserDataHandler19.6.1.6. DOMError19.6.1.7. DOMErrorHandler19.6.1.8. DOMLocator19.6.1.9. DOMConfiguration
21.5.1.1. Document21.5.1.2. Character range21.5.1.3. Whitespace21.5.1.4. Names and tokens21.5.1.5. Literals21.5.1.6. Character data21.5.1.7. Comments21.5.1.8. Processing instructions21.5.1.9. CDATA sections21.5.1.10. Prolog21.5.1.11. Document type definition21.5.1.12. External subset21.5.1.13. Standalone document declaration21.5.1.14. Element21.5.1.15. Start-tag21.5.1.16. End-tag21.5.1.17. Content of elements21.5.1.18. Tags for empty elements21.5.1.19. Element type declaration21.5.1.20. Element-content models21.5.1.21. Mixed-content declaration21.5.1.22. Attribute-list declaration21.5.1.23. Attribute types21.5.1.24. Enumerated attribute types21.5.1.25. Attribute defaults21.5.1.26. Conditional section21.5.1.27. Character reference21.5.1.28. Entity reference21.5.1.29. Entity declaration21.5.1.30. External entity declaration21.5.1.31. Text declaration21.5.1.32. Well-formed external parsed entity21.5.1.33. Encoding declaration21.5.1.34. Notation declarations21.5.1.35. Characters
21.6.1.1. Document21.6.1.2. Character range21.6.1.3. Whitespace21.6.1.4. Names and tokens21.6.1.5. Literals21.6.1.6. Character data21.6.1.7. Comments21.6.1.8. Processing instructions21.6.1.9. CDATA sections21.6.1.10. Prolog21.6.1.11. Document type definition21.6.1.12. External subset21.6.1.13. Standalone document declaration21.6.1.14. Element21.6.1.15. Start-tag21.6.1.16. End-tag21.6.1.17. Content of elements21.6.1.18. Tags for empty elements21.6.1.19. Element type declaration21.6.1.20. Element-content models21.6.1.21. Mixed-content declaration21.6.1.22. Attribute-list declaration21.6.1.23. Attribute types21.6.1.24. Enumerated attribute types21.6.1.25. Attribute defaults21.6.1.26. Conditional section21.6.1.27. Character reference21.6.1.28. Entity reference21.6.1.29. Entity declaration21.6.1.30. External entity declaration21.6.1.31. Text declaration21.6.1.32. Well-formed external parsed entity21.6.1.33. Encoding declaration21.6.1.34. Notation declarations
27.1.2.1. C1 controls27.1.2.2. Latin-1

Content preview from XML in a Nutshell, 3rd Edition

Processing Instructions

In HTML, comments are sometimes abused to support nonstandard extensions. For instance, the contents of the script element are sometimes enclosed in a comment to protect it from display by a nonscript-aware browser. The Apache web server parses comments in .shtml files to recognize server-side includes. Unfortunately, these documents may not survive being passed through various HTML editors and processors with their comments and associated semantics intact. Worse yet, it’s possible for an innocent comment to be misconstrued as input to the application.

XML provides the processing instruction as an alternative means of passing information to particular applications that may read the document. A processing instruction begins with <? and ends with ?>. Immediately following the <? is an XML name called the target , possibly the name of the application for which this processing instruction is intended or possibly just an identifier for this particular processing instruction. The rest of the processing instruction contains text in a format appropriate for the applications for which the instruction is intended.

For example, in HTML, a robots META tag is used to tell search-engine and other robots whether and how they should index a page. The following processing instruction has been proposed as an equivalent for XML documents: