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πŸ”— COMEFROM

πŸ”— Computing πŸ”— Computer science

In computer programming, COMEFROM (or COME FROM) is an obscure control flow structure used in some programming languages, originally as a joke. COMEFROM is roughly the opposite of GOTO in that it can take the execution state from any arbitrary point in code to a COMEFROM statement.

The point in code where the state transfer happens is usually given as a parameter to COMEFROM. Whether the transfer happens before or after the instruction at the specified transfer point depends on the language used. Depending on the language used, multiple COMEFROMs referencing the same departure point may be invalid, be non-deterministic, be executed in some sort of defined priority, or even induce parallel or otherwise concurrent execution as seen in Threaded Intercal.

A simple example of a "COMEFROM x" statement is a label x (which does not need to be physically located anywhere near its corresponding COMEFROM) that acts as a "trap door". When code execution reaches the label, control gets passed to the statement following the COMEFROM. This may also be conditional, passing control only if a condition is satisfied, analogous to a GOTO within an IF statement. The primary difference from GOTO is that GOTO only depends on the local structure of the code, while COMEFROM depends on the global structure – a GOTO transfers control when it reaches a line with a GOTO statement, while COMEFROM requires scanning the entire program or scope to see if any COMEFROM statements are in scope for the line, and then verifying if a condition is hit. The effect of this is primarily to make debugging (and understanding the control flow of the program) extremely difficult, since there is no indication near the line or label in question that control will mysteriously jump to another point of the program – one must study the entire program to see if any COMEFROM statements reference that line or label.

Debugger hooks can be used to implement a COMEFROM statement, as in the humorous Python goto module; see below. This also can be implemented with the gcc feature "asm goto" as used by the Linux kernel configuration option CONFIG_JUMP_LABEL. A no-op has its location stored, to be replaced by a jump to an executable fragment that at its end returns to the instruction after the no-op.

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πŸ”— Kevinism

πŸ”— Germany πŸ”— Anthroponymy

Kevinism and Chantalism jokingly describe the tendency of parents in German-speaking areas to name their children with what appears to them to be unusual, exotic-sounding first names.

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πŸ”— Otokichi

πŸ”— Biography πŸ”— United Kingdom πŸ”— Japan πŸ”— Japan/History πŸ”— Japan/Biography

Otokichi (ιŸ³ε‰ or 乙吉), also known as Yamamoto Otokichi and later known as John Matthew Ottoson (1818 – January 1867), was a Japanese castaway originally from the area of Onoura near modern-day Mihama, on the west coast of the Chita Peninsula in Aichi Prefecture.

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πŸ”— Charlieplexing

πŸ”— Computing πŸ”— Electronics πŸ”— Electrical engineering

Charlieplexing (also known as tristate multiplexing, reduced pin-count LED multiplexing, complementary LED drive and crossplexing) is a technique for accessing a large number of LEDs, switches, micro-capacitors or other I/O entities, using very few tri-state logic wires from a microcontroller, these entities being wired as discrete components, x/y arrays, or woven in a diagonally intersecting pattern to form diagonal arrays.

The method uses the tri-state logic capabilities of microcontrollers in order to gain efficiency over traditional multiplexing, each I/O pin being capable, when required, of rapidly changing between the three states, logical 1, logical 0, and high impedance.

This enables these I/O entities (LEDs, switches etc.) to be connected between any two microcontroller I/Os - e.g. with 4 I/Os, each I/O can pair with 3 other I/Os, resulting in 6 unique pairings (1/2, 1/3, 1/4, 2/3, 2/4, 3/4). Only 4 pairings are possible with standard x/y multiplexing (1/3, 1/4, 2/3, 2/4). Also, due to the microcontroller's ability to reverse the polarity of the 6 I/O pairs, the number of LEDS (or diodes) that are uniquely addressable, can be doubled to 12 - adding LEDS 2/1, 3/1, 4/1, 3/2, 4/2 and 4/3.

Although it is more efficient in its use of I/O, a small amount of address manipulation is required when trying to fit Charlieplexing into a standard x/y array.

Other issues that affect standard multiplexing but are exacerbated by Charlieplexing are:

  • consideration of current requirements and the forward voltages of the LEDs.
  • a requirement to cycle through the in-use LEDs rapidly so that the persistence of the human eye perceives the display to be lit as a whole. Multiplexing can generally be seen by a strobing effect and skewing if the eye's focal point is moved past the display rapidly.


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πŸ”— Lipogram

πŸ”— Writing systems

A lipogram (from Ancient Greek: λΡιπογράμματος, leipogrΓ‘mmatos, "leaving out a letter") is a kind of constrained writing or word game consisting of writing paragraphs or longer works in which a particular letter or group of letters is avoided. Extended Ancient Greek texts avoiding the letter sigma are the earliest examples of lipograms.

Writing a lipogram may be a trivial task when avoiding uncommon letters like Z, J, Q, or X, but it is much more challenging to avoid common letters like E, T, or A in the English language, as the author must omit many ordinary words. Grammatically meaningful and smooth-flowing lipograms can be difficult to compose. Identifying lipograms can also be problematic, as there is always the possibility that a given piece of writing in any language may be unintentionally lipogrammatic. For example, Poe's poem The Raven contains no Z, but there is no evidence that this was intentional.

A pangrammatic lipogram is a text that uses every letter of the alphabet except one. For example, "The quick brown fox jumped over the lazy dog" omits the letter S, which the usual pangram includes by using the word jumps.

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πŸ”— The Red One

πŸ”— Novels πŸ”— Novels/Short story

"The Red One" is a short story by Jack London. It was first published in the October 1918 issue of The Cosmopolitan, two years after London's death. The story was reprinted in the same year by MacMillan, in a collection of London's stories of the same name.

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πŸ”— Kintsugi

πŸ”— Visual arts πŸ”— Japan πŸ”— Japan/Culture πŸ”— Collections Care

Kintsugi (ι‡‘ηΆ™γŽ, "golden joinery"), also known as kintsukuroi (金繕い, "golden repair"), is the Japanese art of repairing broken pottery by mending the areas of breakage with lacquer dusted or mixed with powdered gold, silver, or platinum, a method similar to the maki-e technique. As a philosophy, it treats breakage and repair as part of the history of an object, rather than something to disguise.

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πŸ”— Nine-nine-six (996) Working Hour System

πŸ”— Companies πŸ”— China πŸ”— Organized Labour

The 996 working hour system (Chinese: 996ε·₯作刢) is a work schedule commonly practiced by some companies in the People's Republic of China. It derives its name from its requirement that employees work from 9:00 am to 9:00 pm, 6 days per week; i.e. 72 hours per week. A number of Chinese internet companies have adopted this system as their official work schedule. Critics argue that the 996 working hour system is a flagrant violation of Chinese law.

In March 2019 an "anti-996" protest was launched via GitHub.

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πŸ”— Jove (Jonathan's Own Version of Emacs)

πŸ”— Computing πŸ”— Project-independent assessment

JOVE (Jonathan's Own Version of Emacs) is an open-source, Emacs-like text editor, primarily intended for Unix-like operating systems. It also supports MS-DOS and Microsoft Windows. JOVE was inspired by Gosling Emacs but is much smaller and simpler, lacking Mocklisp. It was originally created in 1983 by Jonathan Payne while at Lincoln-Sudbury Regional High School in Massachusetts, United States on a PDP-11 minicomputer. JOVE was distributed with several releases of BSD Unix, including 2.9BSD, 4.3BSD-Reno and 4.4BSD-Lite2.

As of 2022, the latest development release of JOVE is version 4.17.4.4; the stable version is 4.16. Unlike GNU Emacs, JOVE does not support UTF-8.

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πŸ”— Atlantropa

πŸ”— Architecture

Atlantropa, also referred to as Panropa, was a gigantic engineering and colonisation idea devised by the German architect Herman SΓΆrgel in the 1920s and promoted by him until his death in 1952. Its central feature was a hydroelectric dam to be built across the Strait of Gibraltar, which would have provided enormous amounts of hydroelectricity and would have led to the lowering of the surface of the Mediterranean Sea by up to 200 metres (660Β ft), opening up large new lands for settlement, for example in the Adriatic Sea. The project proposed four additional major dams as well:

  • Across the Dardanelles to hold back the Black Sea
  • Between Sicily and Tunisia to provide a roadway and further lower the inner Mediterranean
  • On the Congo River below its Kwah River tributary to refill the Mega-Chad basin around Lake Chad providing fresh water to irrigate the Sahara and creating a shipping lane to the interior of Africa
  • Suez Canal extension and locks to maintain Red Sea connection

SΓΆrgel saw his scheme, projected to take over a century, as a peaceful European-wide alternative to the Lebensraum concepts that later became one of the stated reasons for Nazi Germany's conquest of new territories. Atlantropa would provide land and food, employment, electric power, and most of all, a new vision for Europe and neighbouring Africa.

The Atlantropa movement, through its several decades, was characterised by four constants:

  • Pacifism, in its promises of using technology in a peaceful way;
  • Pan-European sentiment, seeing the project as a way to unite a war-torn Europe;
  • Eurocentric attitudes to Africa (which was to become united with Europe into "Atlantropa" or Eurafrica), and
  • Neo-colonial geopolitics, which saw the world divided into three blocsβ€”America, Asia, and Atlantropa.

Active support was limited to architects and planners from Germany and a number of other primarily northern European countries. Critics derided it for various faults, ranging from lack of any cooperation of Mediterranean countries in the planning to the impacts it would have had on the historic coastal communities left stranded inland when the sea receded. The project reached great popularity in the late 1920s to the early 1930s, and for a short period again, in the late 1940s to the early 1950s, but soon disappeared from general discourse again after SΓΆrgel's death.

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