In computer science Computer science or computing science is the study of the theoretical foundations of information and computation, and of practical techniques for their implementation and application in computer systems. It is frequently described as the systematic study of algorithmic processes that create, describe, and transform information. Computer science, transclusion is the inclusion of a document or part of a document into another document by reference.
For example, an article about a country might include a chart or a paragraph describing that country's agricultural exports from a different article about agriculture. Rather than copying the included data and storing it in two places, a transclusion embodies modular design In systems engineering, modular design — or "modularity in design" — is an approach that subdivides a system into smaller parts that can be independently created and then used in different systems to drive multiple functionalities. Besides reduction in cost (due to lesser customization, and less learning time), and flexibility in, by allowing it to be stored only once (and perhaps corrected and updated if the link type supported that) and viewed in different contexts. The reference also serves to link both articles.
The term was coined by hypertext Hypertext is text displayed on a computer or other electronic device with references to other text that the reader can immediately access, usually by a mouse click or keypress sequence. Apart from running text, hypertext may contain tables, images and other presentational devices. Hypertext is the underlying concept defining the structure of the pioneer Ted Nelson Theodor Holm Nelson is an American sociologist, philosopher, and pioneer of information technology. He coined the terms "hypertext" and "hypermedia" in 1963 and published it in 1965. He also is credited with first use of the words transclusion, virtuality, intertwingularity and teledildonics. The main thrust of his work has in 1982.
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Technical considerations
Context neutrality
Transclusion works better when transcluded sections of text are self-contained, so that the meaning and validity of the text is independent of the context in which it appears. For example, formulations like "as explained in the previous section" are problematic, because the transcluded section may appear in a different context, causing confusion. What constitutes "context neutral" text varies, but often includes things like company information or boilerplate Boilerplate is any text that is or can be reused in new contexts or applications without being changed much from the original. Many computer programmers often use the term boilerplate code. A legal boilerplate is a standard provision in a contract. The term can also be used to describe text that is unnecessary due to its repetitiveness.
Parameterization
Under some circumstances, and in some technical contexts, transcluded sections of text may not require strict adherence to the "context neutrality" principle, because the transcluded sections are capable of parameterization. Parameterization implies the ability to modify certain portions or subsections of a transcluded text depending on exogenous variables that can be changed independently. This is customarily done by supplying a transcluded text with one or more substitution placeholders. These placeholders are then replaced with the corresponding variable values prior to rendering the final transcluded output in context.
History and implementation by Project Xanadu
Nelson (who had also originated the words "hypertext" and "hypermedia Hypermedia is used as a logical extension of the term hypertext in which graphics, audio, video, plain text and hyperlinks intertwine to create a generally non-linear medium of information.This contrasts with the broader term multimedia, which may be used to describe non-interactive linear presentations as well as hypermedia. It is also related to") coined the term "transclusion" in his 1982 book, Literary Machines Literary Machines is a book first published in 1980 by Ted Nelson, and republished 9 times by 1993. It offers an extensive overview of Nelson's term "hypertext" as well as Nelson's Project Xanadu. It also includes other theories by Nelson, including "tumblers" for addressing bits in files past and present, "transclusion&. Part of his proposal was the idea that micropayments Micropayments are financial transactions involving very small sums of money. PayPal defines a micropayment as a transaction of less than 12 USD, and offers reduced fees for micropayment transactions. A problem that has prevented the emergence of feasible micropayment systems that allow payments of less than 1 USD is a need to keep costs for could be automatically exacted from the reader for all the text, no matter how many snippets of content are taken from various places.
However, according to Nelson, the concept of transclusion had already formed part of his 1965 description[1] of hypertext Hypertext is text displayed on a computer or other electronic device with references to other text that the reader can immediately access, usually by a mouse click or keypress sequence. Apart from running text, hypertext may contain tables, images and other presentational devices. Hypertext is the underlying concept defining the structure of the; he also interprets the notion of "trails" in Vannevar Bush Vannevar Bush was an American engineer and science administrator known for his work on analog computing, his political role in the development of the atomic bomb as a primary organizer of the Manhattan Project, and the idea of the memex, an adjustable microfilm-viewer which is somewhat analogous to the structure of the World Wide Web. As Director's 1945 essay As We May Think As We May Think is an essay by Vannevar Bush, first published in The Atlantic Monthly in July 1945, and republished again as an abridged version in September 1945 — therefore, before and after the U.S. nuclear attacks on Japan. Bush expresses his concern for the direction of scientific efforts towards destruction, rather than understanding, and as describing transclusion rather than hyperlinks In computing, a hyperlink is a reference to a document that the reader can directly follow, or that is followed automatically[citation needed]. The reference points to a whole document or to a specific element within a document. Hypertext is text with hyperlinks. Such text is usually viewed with a computer. A software system for viewing and.[2]
Nelson defines transclusion as "the same content knowably in more than one place", setting it apart from more special cases such as the inclusion of content stored in a different location (which he calls "transdelivery") or "explicit quotation A quotation is the repetition of one expression as part of another one, particularly when the quoted expression is well-known or explicitly attributed to its original source, and it is indicated by (punctuated with) quotation marks which remains connected to its origins" (which he calls "transquotation").[2]
Some hypertext systems, including Ted Nelson's own Xanadu Project Project Xanadu was the first hypertext project, founded in 1960 by Ted Nelson; it is still ongoing. Administrators of Project Xanadu have declared it an improvement over the World Wide Web, saying "Today's popular software simulates paper. The World Wide Web trivialises our original hypertext model with one-way ever-breaking links and no, support transclusion.
Nelson has delivered a demonstration of Web transclusion, the Little Transquoter (programmed to Nelson's specification by Andrew Pam in 2004-2005).[3] It creates a new format built on portion addresses from Web pages; when dereferenced, each portion on the resulting page remains click-connected to its original context—always a key aspect of transclusion for Nelson, but missing in most implementations of transclusion.
Implementations on the Web
HTML
At present[update], transclusion in HTML HTML, which stands for HyperText Markup Language, is the predominant markup language for web pages. It provides a means to create structured documents by denoting structural semantics for text such as headings, paragraphs, lists, links, quotes and other items. It allows images and objects to be embedded and can be used to create interactive forms is somewhat limited by lack of standards support in web browsers A web browser is a software application for retrieving, presenting, and traversing information resources on the World Wide Web. An information resource is identified by a Uniform Resource Identifier and may be a web page, image, video, or other piece of content. Hyperlinks present in resources enable users to easily navigate their browsers to. Although all graphical browsers can transclude an image Inline linking is the use of a linked object, often an image, from one site into a web page belonging to a second site. The second site is said to have an inline link to the site where the object is located, including a document is a bit more difficult. There are currently two methods of achieving this result:
- The IFrame An HTML element is an individual component of an HTML document. HTML documents are composed of a tree of HTML elements and other nodes, such as text nodes. Each element can have attributes specified. Elements can also have content, including other elements and text. HTML elements represent semantics, or meaning. For example, the title element (inline frame) element, which includes whole documents.
- The Object An HTML element is an individual component of an HTML document. HTML documents are composed of a tree of HTML elements and other nodes, such as text nodes. Each element can have attributes specified. Elements can also have content, including other elements and text. HTML elements represent semantics, or meaning. For example, the title element element. In Firefox Mozilla Firefox is a free and open source web browser descended from the Mozilla Application Suite and managed by Mozilla Corporation. As of June 2010[update], Firefox was the second most widely used browser, with 23.81% of worldwide usage share of web browsers, according to Net Applications. Other sources put Firefox's usage share between 20% and and other browsers, this allows true document transclusion, enabling one page to be built from several smaller documents.
In addition, Ajax Ajax is a group of interrelated web development techniques used on the client-side to create interactive web applications. With Ajax, web applications can retrieve data from the server asynchronously in the background without interfering with the display and behavior of the existing page. The use of Ajax techniques has led to an increase in can achieve a similar result across all modern, JavaScript JavaScript is an implementation of the ECMAScript language standard and is typically used to enable programmatic access to computational objects within a host environment. It can be characterized as a prototype-based object-oriented scripting language that is dynamic, weakly typed and has first-class functions. It is also considered a functional-enabled browsers.
Future versions of HTML may support deeper transclusion of portions of documents using XML XML is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards technologies such as entities In the Standard Generalized Markup Language , an entity is a primitive data type, which associates a string with either a unique alias (such as a user-specified name) or an SGML reserved word (such as #DEFAULT). Entities are foundational to the organizational structure and definition of SGML documents. The SGML specification defines numerous, XPointer XPointer is divided among four specifications: a "framework" which forms the basis for identifying XML fragments, a positional element addressing scheme, a scheme for namespaces, and a scheme for XPath-based addressing. XPointer Framework is a recommendation since March 2003 document referencing, and XSLT XSLT is a declarative, XML-based language used for the transformation of XML documents into other XML documents. The original document is not changed; rather, a new document is created based on the content of an existing one. The new document may be serialized (output) by the processor in standard XML syntax or in another format, such as HTML or manipulations. (XPointer is patent-encumbered.)
The practice of 'remote loading'—including data, such as images, directly from other sites—is usually frowned upon because of the use of bandwidth and computing power required from the remote computer system (see Bandwidth theft Inline linking is the use of a linked object, often an image, from one site into a web page belonging to a second site. The second site is said to have an inline link to the site where the object is located). This is said to "tax" another server In computing, a server is any combination of hardware or software designed to provide services to clients. When used alone, the term typically refers to a computer which may be running a server operating system, but is also used to refer to any software or dedicated hardware capable of providing services, and is often considered an example of leeching. Increased distribution of proxy servers In computer networks, a proxy server is a server that acts as an intermediary for requests from clients seeking resources from other servers. A client connects to the proxy server, requesting some service, such as a file, connection, web page, or other resource, available from a different server. The proxy server evaluates the request according to has the potential to turn this around and take advantage of transclusion to reduce redundant transmissions of the same data.
A major exception to this rule is web advertising Advertising is a form of communication intended to persuade an audience to purchase or take some action upon products, ideals, or services. It includes the name of a product or service and how that product or service could benefit the consumer, to persuade a target market to purchase or to consume that particular brand. These brands are usually, where advertisements supplied by an advertiser are published with other content by a publisher. An advertiser prefers to serve an advertisement and be able to detect when it was viewed, rather than have it served by the publisher and have to trust the publisher. (See also Hit counter A web counter or hit counter is a computer software program that indicates the number of visitors, or hits, a particular webpage has received. Once set up, these counters will be incremented by one every time the web page is accessed in a web browser, Web bug A web bug is an object that is embedded in a web page or e-mail and is usually invisible to the user but allows checking that a user has viewed the page or e-mail. One common use is in e-mail tracking. Alternative names are web beacon, tracking bug, tracking pixel, pixel tag, 1×1 gif, and clear gif).
Mashups and meshups To be able to permanently access the data of other services, mashups are generally client applications or hosted online. In the past years, more and more web applications provide APIs that enable software developers to easily integrate data and functions instead of building it themselves. Mashups can be considered to have an active role in the are a recent phenomenon similar to transclusion.
Server-side transclusion
Transclusion can also be accomplished on the server side, provided the server software includes this functionality. This can be done through multiple different technologies, including Server Side Includes Server Side Includes is a simple interpreted server-side scripting language used almost exclusively for the web and markup entity references In the Standard Generalized Markup Language , an entity is a primitive data type, which associates a string with either a unique alias (such as a user-specified name) or an SGML reserved word (such as #DEFAULT). Entities are foundational to the organizational structure and definition of SGML documents. The SGML specification defines numerous resolved by the server software. It is a feature of . Client-side transclusion is generally preferable as data transcluded into several pages can be cached by the client rather than sent out again for every page.
Transclusion of source code into HTML or wiki documents
In order to produce some kinds of software documents (external documents, such as design documents), it is often important to include source code fragments in the text. The transclusion of source code into the documents is an economic and elegant way of preserving the semantic consistency of the inserted code in relation to its source codebase.
Crystalbox provides a simple and easy to use mechanism to support transclusion of source code directly from source code repositories (CVS, Subversion, Git, etc) into any piece of HTML code, wiki text, blog, etc.
References
- ^ Theodor H. Nelson, "A File Structure for the Complex, the Changing and the Indeterminate." Proceedings of the ACM 20th National Conference (1965), pp. 84-100
- ^ a b Theodor Holm Nelson and Robert Adamson Smith: Back To The Future: Hypertext the Way It Used To Be
- ^ The Little Transquoter Xanadu.com.au
Further reading
- Di Iorio, A.; Vitali, F. (August 2003). "A Xanalogical Collaborative Editing Environment" (PDF). Proceedings of the Second International Workshop of Web Document Analysis 2003 (WDA2003). Edinburgh, UK. http://www.csc.liv.ac.uk/~wda2003/Papers/Section_III/Paper_11.pdf.
- Kolbitsch, J.; Maurer, H. (June 2006). "Transclusions in an HTML-Based Environment". Journal of Computing and Information Technology 14 (2): 161–174. doi A digital object identifier is a character string used to uniquely identify an electronic document or other object. Metadata about the object is stored in association with the DOI name and this metadata may include a location, such as a URL, where the object can be found. The DOI for a document is permanent, whereas its location and other metadata:10.2498/cit.2006.02.07. http://cit.zesoi.fer.hr/browseIssue.php?issue=25.
- Kolbitsch, J. (June 2005). "Fine-Grained Transclusions of Multimedia Documents in HTML". Journal of Universal Computer Science 11 (6). http://www.jucs.org/jucs_11_6/fine_grained_transclusions_of/.
- Krottmaier, H. (2002). "Transcluded Documents: Advantages of Reusing Document Fragments" (PDF). Proceedings of the 6th International ICCC/IFIP Conference on Electronic Publishing (ELPUB2002). Czech Republic: Karlovy Vary. pp. 359–367. http://hkrott.iicm.edu/docs/publications/elpub-2002.pdf.
- Krottmaier, H.; D., Helic (2002). "Issues of Transclusions" (PDF). Proceedings of the World Conference on E-Learning in Corporate, Government, Healthcare, & Higher Education (E-Learn 2002). Montreal, Canada. pp. 1730–1733. http://coronet.iicm.edu/denis/pubs/elearn2002b.pdf.
- Krottmaier, H.; Maurer, H. (July 2001). "Transclusions in the 21st Century" (PDF Portable Document Format is an open standard for document exchange. The file format created by Adobe Systems in 1993 is used for representing two-dimensional documents in a manner independent of the application software, hardware, and operating system. Each PDF file encapsulates a complete description of a fixed-layout 2D document that includes, HTML HTML, which stands for HyperText Markup Language, is the predominant markup language for web pages. It provides a means to create structured documents by denoting structural semantics for text such as headings, paragraphs, lists, links, quotes and other items. It allows images and objects to be embedded and can be used to create interactive forms, PostScript PostScript is a dynamically typed concatenative programming language created by John Warnock and Charles Geschke in 1982. PostScript is best known for its use as a page description language in the electronic and desktop publishing areas). Journal of Universal Computer Science 7 (12): 1125–1136. http://www.jucs.org/jucs_7_12/transclusions_in_the_21st/.
- Moore, A.; et al. (2001). "Personally tailored teaching in WHURLE using conditional translucion". Proceedings of the Twelfth ACM Conference on Hypertext and Hypermedia. Aarhus, Danmark. pp. 163–164.
- Nelson, T. H. (1981). Literary Machines. Mindful Press.
- Nelson, T. H. (1995). "The Heart of Connection: Hypermedia Unified by Transclusion". Communications of the ACM 38 (8): 31–33. doi A digital object identifier is a character string used to uniquely identify an electronic document or other object. Metadata about the object is stored in association with the DOI name and this metadata may include a location, such as a URL, where the object can be found. The DOI for a document is permanent, whereas its location and other metadata:10.1145/208344.208353.
- Nelson, T. H. (1996). "Generalized Links, Micropayment and Transcopyright". Almaden Research Center IBM's Almaden Research Center in San Jose, California is one of IBM's eight worldwide research labs. Its scientists perform basic and applied research in computer science, services, storage systems, physical sciences, and materials science and technology. Opened in 1986, the Almaden lab continues the IBM Research legacy started in San Jose more. http://www.almaden.ibm.com/almaden/npuc97/1996/tnelson.htm.
- Nelson, T. H. (1998). "Transcopyright: Pre-Permission for Virtual Republishing". http://www.aus.xanadu.com/xanadu/transcopy.html.
- Nelson, T. H. (1999). "Xanalogical Structure, Needed Now More than Ever: Parallel Documents, Deep Links to Content, Deep Versioning and Deep Re-Use". ACM Computing Surveys 31 (4es): 33. doi A digital object identifier is a character string used to uniquely identify an electronic document or other object. Metadata about the object is stored in association with the DOI name and this metadata may include a location, such as a URL, where the object can be found. The DOI for a document is permanent, whereas its location and other metadata:10.1145/345966.346033. http://xanadu.com.au/ted/XUsurvey/xuDation.html.
- Pam, A. (1997). "Fine-Grained Transclusion in the Hypertext Markup Language" (Text). Internet Draft. http://tools.ietf.org/html/draft-pam-html-fine-trans.
- Wilde, E.; Lowe, D. (2002). "XML Linking Language" (PDF). XPath, XLink, XPointer, and XML: A Practical Guide to Web Hyperlinking and Transclusion. Addison-Wesley Professional. pp. 169–198. http://searchwebservices.techtarget.com/searchWebServices/downloads/wilde-lowe_07.pdf.
See also
- Compound document
- Cross-reference A cross-reference is an instance within a document which refers to related or synonymous information elsewhere, usually within the same work. To cross-reference or to cross-refer (verb) is to make such connections. The term "cross-reference" is often abbreviated as x-ref, xref, or, in computer science, XR. Cross-referencing is usually
- Macro A macro in computer science is a rule or pattern that specifies how a certain input sequence (often a sequence of characters) should be mapped to an output sequence (also often a sequence of characters) according to a defined procedure. The mapping process that instantiates (transforms) a macro into a specific output sequence is known as macro
- Object Linking and Embedding Object Linking and Embedding is a technology that allows embedding and linking to documents and other objects developed by Microsoft. For developers, it brought OLE Control eXtension (OCX), a way to develop and use custom user interface elements. On a technical level, an OLE object is any object that implements the IOleObject interface, possibly
- Publish and Subscribe
- Single source publishing
- Subroutine In computer science, a subroutine is a portion of code within a larger program, which performs a specific task and is relatively independent of the remaining code
External links
- Ted Nelson: Transclusion: Fixing Electronic Literature Google Tech Talks January 29, 2007
Categories: HTML | Hypertext Categories: Electronic literature | Intertextuality | Human-computer interaction | User interface | Hypermedia | Metadata | Ted Nelson
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Wed, 24 Mar 2010 21:24:38 GM
XPath, XLink, XPointer, and XML: A Practical Guide to Web Hyperlinking and . Transclusion. Publisher: Pearson Education | ISBN: 0201703440 | edition 2002 | PDF | 205 pages | 13,3 mb. The combination of Extensible Markup Language (XML) and ...
