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🔗 Computing 🔗 Computer science

In functional programming, continuation-passing style (CPS) is a style of programming in which control is passed explicitly in the form of a continuation. This is contrasted with direct style, which is the usual style of programming. Gerald Jay Sussman and Guy L. Steele, Jr. coined the phrase in AI Memo 349 (1975), which sets out the first version of the Scheme programming language.John C. Reynolds gives a detailed account of the numerous discoveries of continuations.

A function written in continuation-passing style takes an extra argument: an explicit "continuation"; i.e., a function of one argument. When the CPS function has computed its result value, it "returns" it by calling the continuation function with this value as the argument. That means that when invoking a CPS function, the calling function is required to supply a procedure to be invoked with the subroutine's "return" value. Expressing code in this form makes a number of things explicit which are implicit in direct style. These include: procedure returns, which become apparent as calls to a continuation; intermediate values, which are all given names; order of argument evaluation, which is made explicit; and tail calls, which simply call a procedure with the same continuation, unmodified, that was passed to the caller.

Programs can be automatically transformed from direct style to CPS. Functional and logic compilers often use CPS as an intermediate representation where a compiler for an imperative or procedural programming language would use static single assignment form (SSA). SSA is formally equivalent to a subset of CPS (excluding non-local control flow, which does not occur when CPS is used as intermediate representation). Functional compilers can also use A-normal form (ANF) (but only for languages requiring eager evaluation), rather than with 'thunks' (described in the examples below) in CPS. CPS is used more frequently by compilers than by programmers as a local or global style.

🔗 United States 🔗 Biography 🔗 Mathematics 🔗 United States/Vermont

Zerah Colburn (September 1, 1804 – March 2, 1840) was a child prodigy of the 19th century who gained fame as a mental calculator.

Clicking on the first link in the main text of a Wikipedia article, and then repeating the process for subsequent articles, would usually lead to the Philosophy article. As of February 2016, 97% of all articles in Wikipedia eventually led to the article Philosophy. The remaining articles lead to an article without any outgoing wikilinks, to pages that do not exist, or get stuck in loops. This has gone up from 94.52% in 2011.

There have been some theories on this phenomenon, with the most prevalent being the tendency for Wikipedia pages to move up a "classification chain." According to this theory, the Wikipedia Manual of Style guidelines on how to write the lead section of an article recommend that the article should start by defining the topic of the article, so that the first link of each page will naturally take the reader into a broader subject, eventually ending in wide-reaching pages such as Mathematics, Science, Language, and of course, Philosophy, nicknamed "the mother of all sciences".

🔗 Computing

Telescript is an Agent-oriented programming language written by General Magic as part of the overall Magic Cap system. Telescript programs used a modified C-like syntax known as High Telescript and were compiled to a stack-based language called Low Telescript for execution. Low Telescript ran within virtual machine interpreters, or "Telescript engines", on host computers.

The basic model of Telescript is similar to Java, and differs primarily in where the applications would run. Java was modelled to make it possible to download Java applications onto any platform and run them locally. Telescript essentially reversed this, allowing end-user equipment with limited capabilities to upload Telescript programs to servers to allow them to take advantage of the server's capabilities. Telescript could even migrate a running program; the language included features to marshal a program's code and serialized state, transfer it to another Telescript engine (on a device or a server) to continue execution, and finally return to the originating client or server device to deliver its output.

General Magic had originally developed as a team within Apple Inc., and were spun off in 1990. When they began to generate some press buzz in 1992, Apple decided to enter the same market with their Newton tablet computer. General Magic were unable to find a niche within the market, and Telescript services were soon deprecated in favor of new products unrelated to mobile computing.

🔗 Religion 🔗 China 🔗 Visual arts

The Vinegar Tasters (三酸圖; 'three sours'; 嘗醋翁; 'vinegar tasting old-men'; 嘗醋圖, 尝醋图) is a traditional subject in Chinese religious painting. The allegorical composition depicts the three founders of China's major religious and philosophical traditions: Confucianism, Buddhism, and Taoism. The theme in the painting has been interpreted as favoring Taoism and critical of the others.

The three men are dipping their fingers in a vat of vinegar and tasting it; one man reacts with a sour expression, one reacts with a bitter expression, and one reacts with a sweet expression. The three men are Confucius, Buddha, and Laozi, respectively. Each man's expression represents the predominant attitude of his philosophy: Confucianism saw life as sour, in need of rules to correct the degeneration of people; Buddhism saw life as bitter, dominated by pain and suffering due to desires; and Taoism saw life as fundamentally perfect in its natural state. Another interpretation of the painting is that, since the three men are gathered around one vat of vinegar, the "three teachings" are one.

🔗 Africa 🔗 Africa/Tanzania 🔗 Primates

The Gombe Chimpanzee War was a violent conflict between two communities of chimpanzees in Gombe Stream National Park in Tanzania lasting from 1974 to 1978. The two groups were once unified in the Kasakela community. By 1974, researcher Jane Goodall noticed the community splintering. Over a span of eight months, a large party of chimpanzees separated themselves into the southern area of Kasakela and were renamed the Kahama community. The separatists consisted of six adult males, three adult females and their young. The Kasakela was left with eight adult males, twelve adult females and their young.

During the four-year conflict, all males of the Kahama community were killed, effectively disbanding the community. The victorious Kasakela then expanded into further territory but were later repelled by another community of chimpanzees.

🔗 United States 🔗 Medicine 🔗 Oregon 🔗 Crime 🔗 Religion 🔗 Biology 🔗 Terrorism

The 1984 Rajneeshee bioterror attack was the food poisoning of 751 individuals in The Dalles, Oregon, through the deliberate contamination of salad bars at ten local restaurants with Salmonella. A group of prominent followers of Bhagwan Shree Rajneesh (later known as Osho) led by Ma Anand Sheela had hoped to incapacitate the voting population of the city so that their own candidates would win the 1984 Wasco County elections. The incident was the first and is the single largest bioterrorist attack in United States history.

Having previously gained political control of Antelope, Oregon, Rajneesh's followers, who were based in nearby Rajneeshpuram, sought election to two of the three seats on the Wasco County Circuit Court that were up for election in November 1984. Fearing they would not gain enough votes, some Rajneeshpuram officials decided to incapacitate voters in The Dalles, the largest population center in Wasco County. The chosen biological agent was Salmonella enterica Typhimurium, which was first delivered through glasses of water to two County Commissioners and then, on a larger scale, at salad bars and in salad dressing.

As a result of the attack, 751 people contracted salmonellosis, 45 of whom were hospitalized, but none died. Although an initial investigation by the Oregon Public Health Division and the Centers for Disease Control did not rule out deliberate contamination, the agents and contamination were only confirmed a year later. On February 28, 1985, Congressman James H. Weaver gave a speech in the United States House of Representatives in which he "accused the Rajneeshees of sprinkling Salmonella culture on salad bar ingredients in eight restaurants".

At a press conference in September 1985, Rajneesh accused several of his followers of participation in this and other crimes, including an aborted plan in 1985 to assassinate a United States Attorney, and he asked state and federal authorities to investigate. Oregon Attorney General David B. Frohnmayer set up an interagency task force, composed of Oregon State Police and the Federal Bureau of Investigation, and executed search warrants in Rajneeshpuram. A sample of bacteria matching the contaminant that had sickened the town residents was found in a Rajneeshpuram medical laboratory. Two leading Rajneeshpuram officials were convicted on charges of attempted murder and served 29 months of 20-year sentences in a minimum-security federal prison.

🔗 Statistics 🔗 Sociology

The Anna Karenina principle states that a deficiency in any one of a number of factors dooms an endeavor to failure. Consequently, a successful endeavor (subject to this principle) is one where every possible deficiency has been avoided.

The name of the principle derives from Leo Tolstoy's book Anna Karenina, which begins:

All happy families are alike; each unhappy family is unhappy in its own way.

In other words: happy families share a common set of attributes which lead to happiness, while any of a variety of attributes can cause an unhappy family. This concept has been generalized to apply to several fields of study.

In statistics, the term Anna Karenina principle is used to describe significance tests: there are any number of ways in which a dataset may violate the null hypothesis and only one in which all the assumptions are satisfied.

🔗 Cryptography 🔗 Cryptography/Computer science 🔗 Judaism

Atbash (Hebrew: אתבש‎; also transliterated Atbaš) is a monoalphabetic substitution cipher originally used to encrypt the Hebrew alphabet. It can be modified for use with any known writing system with a standard collating order.

🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Philately 🔗 Libraries 🔗 Military history/World War II 🔗 Military history/European military history 🔗 Military history/British military history

V-mail, short for Victory Mail, was a hybrid mail process used by the United States during the Second World War as the primary and secure method to correspond with soldiers stationed abroad. To reduce the cost of transferring an original letter through the military postal system, a V-mail letter would be censored, copied to film, and printed back to paper upon arrival at its destination. The V-mail process is based on the earlier British Airgraph process.