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🔗 Continuation-Passing Style

🔗 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.

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🔗 Choking game, also known as the fainting game

🔗 Medicine

The choking game (also known as the fainting game and a wide variety of slang terms) refers to intentionally cutting off oxygen to the brain with the goal of inducing temporary loss of consciousness and euphoria.

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🔗 Molle

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory

MOLLE (pronounced , similar in pronunciation to the name Molly) is an acronym for Modular Lightweight Load-carrying Equipment. It is used to define the current generation of load-bearing equipment and backpacks used by a number of NATO armed forces, especially the British Army and the United States Army.

The system's modularity is derived from the use of Pouch Attachment Ladder System (PALS) webbing equipment as rows of heavy-duty nylon stitched onto the vest to allow for the attachment of various compatible pouches and accessories. This method of attachment has become a de facto standard for modular tactical gear, replacing the All-purpose Lightweight Individual Carrying Equipment (ALICE) system used in the earliest modular vest systems (which is still in use with many police forces).

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  • "Molle" | 2022-04-03 | 12 Upvotes 2 Comments

🔗 Sexy prime

🔗 Mathematics

Sexy primes are prime numbers that differ from each other by 6. For example, the numbers 5 and 11 are both sexy primes, because 11 - 5 = 6.

The term "sexy prime" is a pun stemming from the Latin word for six: sex.

If p + 2 or p + 4 (where p is the lower prime) is also prime, then the sexy prime is part of a prime triplet.

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🔗 Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz

🔗 Germany

Rinderkennzeichnungs- und Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz listen  (RkReÜAÜG) (literally, Cattle marking and beef labeling supervision duties delegation law) was a law of the German state of Mecklenburg-Vorpommern of 1999, repealed in 2013. It dealt with the supervision of the labeling of beef.

The name is an example of the virtually unlimited compounding of nouns that is possible in many Germanic languages. German orthography uses "closed" compounds, concatenating nouns to form one long word. This is unlike most English compounds, which are separated using spaces or hyphens.

Strictly speaking, it is made up of two words, because a hyphen at the end of a word is used to show that the word will end in the same way as the following. Consequently, the two words would be Rinderkennzeichnungsüberwachungsaufgabenübertragungsgesetz and Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz.

This is the official short title of the law; its full name is Gesetz zur Übertragung der Aufgaben für die Überwachung der Rinderkennzeichnung und Rindfleischetikettierung, corresponding to Law on delegation of duties for supervision of cattle marking and beef labeling. Most German laws have a short title consisting of a composite noun.

Words as long as this are not at all common in German. When the law was proposed in the state parliament, the members reacted with laughter and the responsible minister Till Backhaus apologized for the "possibly excessive length". In 1999, the German Language Society nominated Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz for its Word of the Year award, but it lost to das Millennium, a Latin word that gained in usage at that time, complementing the German word for millennium, Jahrtausend.

In 2003, a decree was established that modified some real estate-related regulations; its name was longer than the above law: Grundstücksverkehrsgenehmigungszuständigkeitsübertragungsverordnung (long title: Verordnung zur Übertragung der Zuständigkeiten des Oberfinanzpräsidenten der Oberfinanzdirektion Berlin nach § 8 Satz 2 der Grundstücksverkehrsordnung auf das Bundesamt zur Regelung offener Vermögensfragen, GrundVZÜV), roughly Regulation on the delegation of authority concerning land conveyance permissions. At 67 letters, it surpassed the RkReÜAÜG, but was repealed in 2007.

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🔗 Illegal prime

🔗 Computing 🔗 Mathematics 🔗 Crime 🔗 Cryptography 🔗 Cryptography/Computer science

An illegal prime is a prime number that represents information whose possession or distribution is forbidden in some legal jurisdictions. One of the first illegal primes was found in 2001. When interpreted in a particular way, it describes a computer program that bypasses the digital rights management scheme used on DVDs. Distribution of such a program in the United States is illegal under the Digital Millennium Copyright Act. An illegal prime is a kind of illegal number.

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🔗 Father of the moderm tiling WMs proposed for deletion in Wikipedia.

🔗 Computing 🔗 Computing/Software

dwm is a dynamic, minimalist tiling window manager for the X Window System that has influenced the development of several other X window managers, including xmonad and awesome. It is externally similar to wmii, but internally much simpler. dwm is written purely in C for performance and security in addition to simplicity, and lacks any configuration interface besides editing the source code. One of the project's guidelines is that the source code is intended to never exceed 2000 SLOC, and options meant to be user-configurable are all contained in a single header file.

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🔗 Conjugate Acids and Bases

🔗 Chemistry

A conjugate acid, within the Brønsted–Lowry acid–base theory, is a chemical compound formed when an acid donates a proton (H+) to a base—in other words, it is a base with a hydrogen ion added to it, as in the reverse reaction it loses a hydrogen ion. On the other hand, a conjugate base is what is left over after an acid has donated a proton during a chemical reaction. Hence, a conjugate base is a species formed by the removal of a proton from an acid, as in the reverse reaction it is able to gain a hydrogen ion. Because some acids are capable of releasing multiple protons, the conjugate base of an acid may itself be acidic.

In summary, this can be represented as the following chemical reaction:

Johannes Nicolaus Brønsted and Martin Lowry introduced the Brønsted–Lowry theory, which proposed that any compound that can transfer a proton to any other compound is an acid, and the compound that accepts the proton is a base. A proton is a nuclear particle with a unit positive electrical charge; it is represented by the symbol H+ because it constitutes the nucleus of a hydrogen atom, that is, a hydrogen cation.

A cation can be a conjugate acid, and an anion can be a conjugate base, depending on which substance is involved and which acid–base theory is the viewpoint. The simplest anion which can be a conjugate base is the solvated electron whose conjugate acid is the atomic hydrogen.

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🔗 Arabic Wikipedia Blackout

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🔗 The Expert at the Card Table: The Classic Treatise on Card Manipulation

🔗 Books 🔗 Magic

The Expert at the Card Table, originally titled Artifice, Ruse and Subterfuge at the Card Table: A Treatise on the Science and Art of Manipulating Cards, often referred to simply as Erdnase, is an extensive book on the art of sleight of hand published in 1902 by S. W. Erdnase, a pseudonymous author whose identity has remained a mystery for over a century. As a detailed manual of card sharps, the book is considered to be one of the most influential works on magic or conjuring with cards.

The Expert at the Card Table is the most famous, the most carefully studied book ever published on the art of manipulating cards at gaming tables."

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