Literate programming increases product quality by requiring software developers to examine and explain their code. A complex piece of software consists of simple parts and simple relations between those parts; the programmer's task is to state those parts and those relationships, in whatever order is best for human comprehension not in some rigidly determined order like top-down or bottom-up." It is well known for its simplicity and it allows for text formatting in HTML rather than going through the TeX system. lack actual macro expansion (docco and friends, literatehaskell) outdated and difficult to build. [17] This example provides a good illustration of the basic elements of literate programming. [1] The approach is used in scientific computing and in data science routinely for reproducible research and open access purposes. Actually, writing out the expanded source code can be done from any section or subsection (i.e. Literate programmingis a way to write programs prioritized for understanding. And the fact that there's no need to be hung up on the question of top-down versus bottom-up, since a programmer can now view a large program as a web, to be explored in a psychologically correct order is perhaps the greatest lesson I have learned from my recent experiences. Literate programming is very often misunderstood[12] to refer only to formatted documentation produced from a common file with both source code and comments – which is properly called documentation generation – or to voluminous commentaries included with code. 0 ° ´ @ &. Nœ6?°§¥¬‰a™?|Ùþ„þ2ò%À ñ…lÕ McIlroy later admitted that his critique was unfair, since he criticized Knuth's program on engineering grounds, while Knuth's purpose was only to demonstrate the literate programming technique. Knuth presented a CWEB version of this example in Chapter 12 of his Literate Programming book. This implementation was called "WEB" by Knuth since he believed that it was one of the few three-letter words of English that hadn't already been applied to computing. It involves writing code and documentation in a single source document, ordered for comprehension by humans rather than computers. Weaving: Generating a comprehensive document about the program and its maintenance. Literate programming is a programming paradigm introduced by Donald Knuth in which a computer program is given an explanation of its logic in a natural language, such as English, interspersed with snippets of macros and traditional source code, from which compilable source code can be generated. The same example was later rewritten for the noweb literate programming tool. The "<<*>>" symbol stands for the "root", topmost node the literate programming tool will start expanding the web of macros from. The approach is used in scientific computing and in data science routinely for reproducible research and open access purposes. McIlroy concluded:[14]. an editor for literate programming. CiteSeerX - Document Details (Isaac Councill, Lee Giles, Pradeep Teregowda): Literate programming was invented by Donald Knuth as a technique for improved documentation of program understanding. Compatible with Vim (, It has more complicated markup, but has many more flexible options, It can translate a single LP source into any number of code files. literate programming provides higher-quality programs, since it forces programmers to explicitly state the thoughts behind the program, making poorly thought-out design decisions more obvious. Applicability of the concept to programming on a large scale, that of commercial-grade programs, is proven by an edition of TeX code as a literate program. If anything, i'd say that Zed's an exemplary member of the community in terms of cranking out code that's easy to follow -AND- has documentation -AND- a manual. This misconception has led to claims that comment-extraction tools, such as the Perl Plain Old Documentation or Java Javadoc systems, are "literate programming tools". [5] While the first generation of literate programming tools were computer language-specific, the later ones are language-agnostic and exist above the programming languages. It is an inverse literate programming tool available as a Ruby Gem. There is less need for elaborate workarounds because of the limitations of C (or Pascal or Assembler). This differs from traditional documentation, in which a programmer is presented with source code that follows a compiler-imposed order, and must decipher the thought process behind the program from the code and its associated comments. Supports the iJulia mode of development which was inspired by iPython. If the code was written with Literate Programming techniques, much of this question/answer would be superflous because the explanation would be included. Knuth says that when he realized this, he began to think of a program as a web of various parts. Literate programming tools are used by millions of programmers today. ", "I chose the name WEB partly because it was one of the few three-letter words of English that hadn't already been applied to computers. Its central tenet is that documentation is more important than source code and should be the focus of a programmer's activity. endstream endobj 316 0 obj <>stream See the generated documentation as HTML. The following snippet of the wc literate program[17] shows how arbitrary descriptive phrases in a natural language are used in a literate program to create macros, which act as new "operators" in the literate programming language, and hide chunks of code or other macros. This anthology of essays from Donald Knuth, "the father of computer science," and the inventor of literate programming includes early essays on related topics such as structured programming, as well as The Computer Journal article that launched literate programming itself. Provides an interactive programming environment that evaluates each statement and displays live results as the code is edited. Literate tools take a literate file and essentially generate two types of files. [2] Literate programming tools are used by millions of programmers today.[3]. The literate programming paradigm, as conceived by Knuth, represents a move away from writing computer programs in the manner and order imposed by the computer, and instead enables programmers to develop programs in the order demanded by the logic and flow of their thoughts. The preprocessor also provides an ability to write out the content of the macros and to add to already created macros in any place in the text of the literate program source file, thereby disposing of the need to keep in mind the restrictions imposed by traditional programming languages or to interrupt the flow of thought. A Case for Contemporary Literate Programming VREDA PIETERSE, DERRICK G. KOURIE AND ANDREW BOAKE University of Pretoria _____ In this paper we discuss the characteristics of Literate Programming and the development of programming environments to support Literate Programming in the past two decades. Docco Next facilitates literate programming in several languages. Literate programming was first introduced by Knuth in 1984. This approach makes it possible for the programmer to create macros that are descriptive and explanatory in nature, based on the though processes of the … Supports TeX equations. It uses "noweb" markup for the literate source files. Ron Isaac. Perhaps a more appropriate title would include Literate Scripting ; regardless, the content I present here is … Supports a limited form of literate programming out of the box. Jul 16, 2015 by Ron Isaac EducationViews Contributor. A preprocessor is used to substitute arbitrary hierarchies, or rather "interconnected 'webs' of macros",[7] to produce the compilable source code with one command ("tangle"), and documentation with another ("weave"). All literate programs consist of prose and literate constructs. The system was developed by Donald Knuth at Stanford University with the purpose of enabling anyone to generate high-quality books, and to develop a system that yields the same results whatever computer is used. Literate programming requires that there is freedom in ordering content in the literate file. This idea has been implemented in a number of modern literate programming tools (Table 1). docco src/*js). He was inspired by the ideas of Pierre-Arnoul de Marneffe. Literate Programming tools can be quite simple if they're focused on modern, high-level object-oriented (or functional) programming languages. It does not have the extensibility of, Respects indentation which makes usable for the languages like. [1], In a noweb literate program besides the free order of their exposition, the chunks behind macros, once introduced with "<<...>>=", can be grown later in any place in the file by simply writing "<>=" and adding more content to it, as the following snippet illustrates ("plus" is added by the document formatter for readability, and is not in the code). TANGLE is able to scramble everything up into the arrangement that a PASCAL compiler demands. “It also makes the program more difficult to change because prose tends to be more tightly interconnected than code. Literate programming is a programming and documentation methodology. According to Knuth,[8][9] He has fashioned a sort of industrial-strength Faberge egg—intricate, wonderfully worked, refined beyond all ordinary desires, a museum piece from the start. The term was coined in 1983 by Donald Knuth to refer to the new way in which he was laying out his software projects. Literate programming uses modern, common language to create scripts. Unlike structured programming, literate programming often makes use of common-day language combined with source code that is considered traditional. Tangling: Generating machine executable code, The Web 68 Literate Programming system used, This page was last edited on 26 December 2020, at 13:17. The … [17], The documentation for a literate program is produced as part of writing the program. Knuth also claims that literate programming provides a first-rate documentation system, which is not an add-on, but is grown naturally in the process of exposition of one's thoughts during a program's creation. [15] In 1987, Communications of the ACM published a followup article which illustrated literate programming with a C program that combined artistic approach of Knuth with engineering approach of McIlroy, with a critique by John Gilbert.[16]. For example, this paragraph is a valid literate program. I do not buy the result. It does it in a single invocation; it does not have separate weave and tangle commands. Literate programming (LP) tools are used to obtain two representations from a literate source file: one suitable for further compilation or execution by a computer, the "tangled" code, and another for viewing as formatted documentation, which is said to be "woven" from the literate source. The first published literate programming environment was WEB, introduced by Knuth in 1981 for his TeX typesetting system; it uses Pascal as its underlying programming language and TeX for typesetting of the documentation. The main intention behind this approach was to treat a program as literature understandable to human beings. It’s a powerful low-level markup and programming language that creates professional quality typeset text. ", Program as a web—macros are not just section names, Order of human logic, not that of the compiler, "I had the feeling that top-down and bottom-up were opposing methodologies: one more suitable for program exposition and the other more suitable for program creation. This idea has subsequently gained a good deal of traction not least because it is powerful and deceptively simple. Already, various thinkers about the future have proposed a number of candidates forthe designation "twenty-first-century literacy." Otherwise, you are restricted to the execution order of the computer. Zed indicates in his essay that he supports literate programming, or at least it's goals. Modula-2 Reloaded – A Modern Typesafe and Literate Programming Language (modula-2.info) ... 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