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🔗 Computing 🔗 Perl

Raku rules are the regular expression, string matching and general-purpose parsing facility of Raku, and are a core part of the language. Since Perl's pattern-matching constructs have exceeded the capabilities of formal regular expressions for some time, Raku documentation refers to them exclusively as regexes, distancing the term from the formal definition.

Raku provides a superset of Perl 5 features with respect to regexes, folding them into a larger framework called rules, which provide the capabilities of a parsing expression grammar, as well as acting as a closure with respect to their lexical scope. Rules are introduced with the rule keyword, which has a usage quite similar to subroutine definitions. Anonymous rules can be introduced with the regex (or rx) keyword, or simply be used inline as regexes were in Perl 5 via the m (matching) or s (substitution) operators.

🔗 Biography 🔗 Science Fiction 🔗 Literature 🔗 Poland 🔗 Biography/arts and entertainment

Stanisław Herman Lem (Polish: [staˈɲiswaf ˈlɛm] (listen); 12 or 13 September 1921 – 27 March 2006) was a Polish writer of science fiction, philosophy, and satire. Lem's books have been translated into 41 languages and have sold over 45 million copies. From the 1950s to 2000s, he published many books, both science fiction and philosophical/futurological. Worldwide, he is best known as the author of the 1961 novel Solaris, which has been made into a feature film three times. In 1976, Theodore Sturgeon wrote that Lem was the most widely read science fiction writer in the world. The total print of Lem's books is over 30 million copies.

Lem's works explore philosophical themes through speculation on technology, the nature of intelligence, the impossibility of communication with and understanding of alien intelligence, despair about human limitations, and humanity's place in the universe. They are sometimes presented as fiction, but others are in the form of essays or philosophical books.

Translating his works is difficult due to passages with elaborate word formation, idiomatic wordplay, alien or robotic poetry, and puns.

🔗 Oregon 🔗 Novels 🔗 Novels/19th century

The Begum's Fortune (French: Les Cinq cents millions de la Bégum, literally "the 500 millions of the begum"), also published as The Begum's Millions, is an 1879 novel by Jules Verne, with some utopian elements and other elements that seem clearly dystopian. It is noteworthy as the first published book in which Verne was cautionary, and somewhat pessimistic about the development of science and technology.

Long after The Begum's Fortune was published, it came out that its story is based on a manuscript by Paschal Grousset, a Corsican revolutionary who had participated in the Paris Commune and was at the time living in exile in the United States and London. It was bought by Pierre-Jules Hetzel, the publisher of most of Verne's books. The attribution of plot elements between Grousset's original text and Verne's work on it has not been completely defined. Later, Verne worked similarly on two more books by Grousset and published them under his name, before the revolutionary finally got a pardon and was able to return to France and resume publication in his own name.

The book first appeared in a hasty and poorly done English translation soon after its publication in French—one of the bad translations considered to have damaged Verne's reputation in the English-speaking world. W. H. G. Kingston was near death and deeply in debt at the time. His wife, Mrs. A. K. Kingston, who did the translation for him, was certainly otherwise preoccupied than with the accuracy of the text and may have had to rely on outside help. In 2005 a new translation from the French was made by Stanford Luce and published by Wesleyan University.

I. O. Evans, in his introduction to his "Fitzroy Edition" of The Begum's Fortune, suggested a connection between the creation of artificial satellites in this novel and the publication of The Brick Moon by Edward Everett Hale in 1869.

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Military history/Cold War 🔗 Pritzker Military Library 🔗 Firearms

The M-28 or M-29 Davy Crockett Weapon System was the tactical nuclear recoilless gun (smoothbore) for firing the M-388 nuclear projectile that was deployed by the United States during the Cold War. It was one of the smallest nuclear weapon systems ever built, with a yield between 10 and 20 tons TNT equivalent (40–80 gigajoules). It is named after American folk hero, soldier, and congressman Davy Crockett.

🔗 Norway

Norsk Data was a (mini-)computer manufacturer located in Oslo, Norway. Existing from 1967 to 1992, it had its most active period in the years from the early 1970s to the late 1980s. At the company's peak in 1987 it was the second largest company in Norway and employed over 4,500 people.

Throughout its history Norsk Data produced a long string of extremely innovative systems, with a disproportionately large number of world firsts. Some examples of this are the NORD-1, the first minicomputer to have memory paging as a standard option, and the first machine to have floating-point instructions standard, the NORD-5, the world's first 32-bit minicomputer (beating the VAX, often claimed the first, by 6 years)

🔗 Biography 🔗 Video games

Zachtronics LLC is an American indie video game studio, best known for their engineering puzzle games and programming games. Zachtronics was founded by Zach Barth in 2000, who serves as its lead designer. Some of their products include SpaceChem, Infinifactory, TIS-100, and Shenzhen I/O.

🔗 Computing 🔗 Computing/Computer hardware 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Computer Security 🔗 Computer Security/Computing 🔗 Computing/Software 🔗 Military history/Intelligence 🔗 Computing/Computer Security 🔗 Computing/Networking

NOBUS ("nobody but us") are security vulnerabilities which the United States National Security Agency (NSA) believes that only it can exploit. As such, NSA sometimes chooses to leave such vulnerabilities open if NSA finds them, in order to exploit them against NSA's targets. More broadly, it refers to the notion that some signals intelligence capabilities are so powerful or otherwise inaccessible that only the NSA will be able to deploy them, though recent analyses suggest that this advantage may be under stress.

🔗 Economics 🔗 Transport

The Downs–Thomson paradox (named after Anthony Downs and John Michael Thomson), also known as the Pigou–Knight–Downs paradox (after Arthur Cecil Pigou and Frank Knight), states that the equilibrium speed of car traffic on a road network is determined by the average door-to-door speed of equivalent journeys taken by public transport.

It is a paradox in that improvements in the road network will not reduce traffic congestion. Improvements in the road network can make congestion worse if the improvements make public transport more inconvenient or if it shifts investment, causing disinvestment in the public transport system.

🔗 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.