Metasyntactic variable

A metasyntactic variable is either a placeholder name (a kind of alias term, commonly used to denote the subject matter under discussion), or a random member of a class of things under discussion. The term originates from computer programming and other technical contexts, and is commonly used in examples by hackers and programmers. The use of a metasyntactic variable is helpful in freeing a programmer from creating a logically named variable, although the invented term may also become sufficiently popular and enter the language as a neologism. The word foo is the canonical example (it is known as the canonical metasyntactical variable).

The phenomenon is similar to the use in algebra of x, y and z for unknown variables, and a, b and c for unknown constants. "Widgets" are also used in business to indicate an as-yet-unspecified product and are frequently sold by the Acme company.

Metasyntactic variables are so called because:

1. They are variables in the metalanguage used to talk about programs, etc. (see also pseudocode);
2. They are variables whose values are often variables (as in usages like "the value of f(foo, bar) is the sum of foo and bar").

Examples

Nonsense words

Foo, Bar, and Baz

Foo is the Canonical Metasyntactic Variable, commonly used to represent an as-yet-unspecified term, value, process, function, destination or event but seldom a person (see Ned Baker, below). It might also be an abbreviation for "File Or Object". It is sometimes combined with bar to make foobar. This suggests that foo may have originated with the World War II slang term fubar, as an acronym for fucked/fouled/"fixed" up beyond all recognition/repair, although the Jargon File makes a reasonably good case [1] that foo predates fubar. Foo was also used as a nonsense word in the surrealistic comic strip Smokey Stover that was popular in the 1940s and 1950s. See also Foo fighter for more foo etymology, as well as RFC 3092.

Another usage of foo is as an abbreviation of the phrase "forward observation officer" (or observer). Apparently FOOs used to go places well forward of normal troops in battle and leave a stylised chalk graffiti of a person looking over a wall with the words "foo was here". (See also: The American version "Kilroy was here.")

The term "Kung foo" (from Kung Fu) has come to mean skill in computer programming. This is actually used (though misspelled) in the movie The Core. This usage itself has spawned variants, such as the GIMP's "Script-Fu" plugin. It is also used to refer to specialized skill regarding a certain programming language or tool, as in "sed fu".

"Foo" can now also just be short for "fool", though its usage as an IT variable predates the ebonic "foo" becoming mainstream.

Bar, the canonical second metasyntactic variable, typically follows foo.

Baz, the canonical third metasyntactic variable, is commonly used after foo and bar. It is also a common Arabic surname, and appears (occasionally in the United Kingdom, more frequently in Australia) as a short form of the forename Barry.

Foo, bar, and baz are often compounded together to make such words as foobar, barbaz, and foobaz.

Gazonk

Gazonk is often used as an alternative for baz or as a third metasyntactic variable. Some early versions of the popular editor Emacs used gazonk.foo as a default filename.

Quux

Quux, introduced by Guy L. Steele, Jr., is the canonical fourth metasyntactic variable, commonly used after baz. However, more recently Qux has become more common as the fourth variable, displacing Quux as the fifth. A probable reason for this is that Quux is often followed by the series Quuux, Quuuux, Quuuuux etc. and Qux fits this pattern perfectly.

Interestingly, in amateur radio, "QUX" means "What is the magnetic course to you?".

Bat

Bat is used by some programmers as an alternative to quuux.

Xyzzy

The word xyzzy is a "magic word" from the Colossal Cave Adventure, and therefore is often used as a metasyntactic variable, especially by old-school hackers. It turns up occasionally in other contexts, such as being the cheat code for Minesweeper on many versions of Microsoft Windows [2].

Shme

Shme is infrequently used in various environments such as Berkeley, GeoWorks, Ingres, Quovadx. Pronounced /shmeh/ with a short /e/.

Zxc

The use of zxc is likely due to the arrangement of the standard QWERTY keyboard, on which Z, X, and C are the first three keys (from left to right) on the bottom row of letters. According to the Jargon File, use of this name can be found at Cambridge University.

RFC 3092

RFC 3092, published on April Fools' Day of 2001, lists the "standard list of metasyntactic variables" as follows: foo, bar, baz, qux, quux, corge, grault, garply, waldo, fred, plugh, xyzzy, thud.

Arfle, barfle, gloop

Used by those from a BBC Micro background. Originated as the response of the parser of a BBC Micro adventure game to input it didn't understand. [3] An example of its use can be seen in this gcc bug report, along with other interesting metasyntactic variables.

English words

Spam and Eggs

Spam and eggs are the canonical metasyntactic variables used in the Python programming language. This is a reference to a famous comedy sketch by Monty Python, after which the language is named.

Needle and Haystack

Needle and haystack are commonly used in computer programming to describe the syntax of functions that involve a search parameter and a search target, such as searching a substring within a string; with these two words, derived from the idiom "to find a needle in a haystack", it is clearer where the substring for which to search goes, and where the string in which to search goes. This can be seen, for instance, in the documentation for some functions in the computer language PHP, see [4] for an example.

Wibble

First recorded in the 1840s alongside wobble, wibble rose to prominence after it was used as a nonsense word in the Roger Irrelevant cartoon strip in UK adult comic Viz in the 1980s and later used in an episode of Blackadder Goes Forth in 1989. The term is also used as a synonym for chatter and other contentless remarks, and (rarely) as a way of pronouncing "www"

Other examples

Other words used as metasyntactic variables include: beekeeper, bing, blarg, bleh, blort, corge, doit, dothestuff, garply, glarb, grault, hoge, kalaa, mum, puppu, stuff, sub, temp, test, thud, var, waldo, momo.

Plugh, like xyzzy, is a "magic word" from the Colossal Cave Adventure. Similarly, blort is the name of a magic potion in Zork.

The term blah is often used because of its use as a placeholder term in common English speech. For example, here is how one might describe casually how to write a letter in colloquial English: "You write 'Dear so-and-so, blah, blah, blah, Sincerely, your name.'"

Standard English uses the word whatever as a metasyntactic word. It is one of the few that is actually in the dictionary as such. Similar to wherever, however, and whenever. Despite being in the dictionary, whatever rarely makes the lists of metasyntactic variables. Using foo for many audiences would require explanation, but using whatever is readily accepted.

Numbers

23

The number 23 is also commonly used as an integer example—particularly when the connotations associated with 42 are undesirable. This number is noted as important in the Principia Discordia due to its relation to The Law of Fives, and is further popularized in the Illuminatus! Trilogy by Robert Anton Wilson and Robert Shea.

42

The number 42 is often a common initializer for integer variables, and acts in the same vein as a "metasyntactic value". It is taken from Douglas Adams' The Hitchhiker's Guide to the Galaxy, where Deep Thought concluded that it was The Answer to Life, the Universe, and Everything.

47

The number 47 is sometimes used instead of 42 above, and is used mainly by members of the 47 society, Chief Delphi members, Pomona College graduates, or New Trek fans.

69

69 is often used as an example number. Popular among hackers as an addition to metasyntactic variables (foo69, bar69), also used in all sorts of hacks. 69 is popular because of its reference to a sexual position. It is also because it is the largest number whose factorial can be calculated by a pocket calculator limited to standard scientific notation with a 2 digit exponent.

666

666 is the Number of the Beast, and often refers to something considered bad or evil.

0815

0815 (named after the repetitive and boring MG 08/15-training) is used in German as either a random number or to reflect something mainstream, normal or boring.

OU812

OU812 ("Oh, you ate one too") is the name of an album by Van Halen, and is often used for its amusing phonetic properties as well as the fact that it contains both letters and numbers, useful for testing alphanumeric fields.

1337

1337 stands for leet, in Leetspeak; because of this positive (or ironic) connotation, it is commonly used.

1701

1701 is often used by Star Trek fan programmers, because of its reference to the Starship Enterprise.

4711

4711 is most commonly used in German computer speak as a random member of a set. It is a brand of Eau de Cologne, originally named after the number of the manufacturer's house in Cologne.

48879

48879 is commonly used as a hexadecimal number where it is represented as "BEEF". It often follows 57005 to form the hexidecimal phrase "DEAD BEEF".

49374

49374 is commonly used as a hexadecimal number where it is represented as "C0DE". It often follows 57005 to form the hexidecimal phrase "DEAD C0DE"; together these numbers are used in places to indicate source code that no longer works or is no longer used.

57005

57005 is commonly used as a hexadecimal number where it is represented as "DEAD".

12648430

12648430 is commonly used as a hexadecimal number where it is represented as "C0FFEE".

Names of people

J. Random and Ned Baker

J. Random and Ned Baker are the names of archetypal users; compare to "The Joneses". J. Random Hacker and J. Random User are also common.

Alice and Bob

Alice and Bob are names of the archetypal individuals used as examples in discussions of cryptographic protocols. Others include:

• Carol - a participant in three- and four-party protocols
• Dave - a participant in four-party protocols
• Ellen - a participant in five- and six-party protocols
• Frank - a participant in six-party protocols, and so on
• Eve or Oscar - an (evil) eavesdropper
• Mallory or Mallet - a malicious active attacker
• Trent - a trusted arbitrator
• Walter - a warden
• Peggy - a prover
• Victor - a verifier
• Sam - a trusted server (Uncle Sam)
• Charlie - a challenger or opponent
• Trudy - an intruder or malicious entity

Bob, Alice and Carol may have come from the 1969 movie Bob & Carol & Ted & Alice, or from the fact that they are common English names starting with A, B and C, the first letters of the alphabet. Dave, Ellen, and Frank are the next three letters. Some people continue this pattern, using Gloria or another similar term for the seventh participant, and so on (maintaining the pattern female, male, female, male...).

Fred and Barney

After the characters in the cartoon series The Flintstones. The most famous use of these is the example code in Learning Perl. Fred is also known to have been used simply because the keys are close together on the QWERTY keyboard.

Romeo and Juliet

JIDs like romeo@montague.net and juliet@capulet.com/balcony are often used in Jabber enhancement proposals in the same way as Alice and Bob

Military names

Some names are most commonly used in military context.

• Private Snuffy
• LCpl Benotz specific to the USMC
• Susie Rottencrotch or Jane Rottencrotch; from the movie Full Metal Jacket
• GI Joe or GI Jane
• Beetle Bailey from the comic strip of the same name
• Gomer Pyle or Private Pyle; from the television show of the same name, also popularized by the movie Full Metal Jacket
• Tommy Atkins, origin of the name "Tommy" for a British soldier
• Private Bloggins, used primarily within the Canadian Forces as an arbitrary person, much like John Smith.

Other names

Sometimes placeholders from other contexts will be used: John Doe, Jane Roe, Richard Roe, A. N. Other, Frick and Frack, John Q. Public, Bloggs or Joe Bloggs (or occasionaly, Fred Bloggs), Joe Soap and Tom, Dick and Harry. In some law schools, the generic case name Push v. Pull is used as a variable. Law or accounting firms are sometimes referred to with names like Dewey, Cheatem, and Howe ("Do we cheat 'em? And how!") Other nonsense names come from swapping initials, e.g. J. Pennings (Peter Jennings).

Place names

Smallville and Metropolis

Smallville and Metropolis are fictional places from the Superman series of comic books. These are used to contrast rural and urban characteristics.

Anywhere, Anytown and Nowhere

Anywhere, USA or Anytown, USA connotes genericness. Nowhere sometimes suggests that the entry is invalid.

Ballybackanowhere

Used in Northern Ireland to denote a small town in the middle of the countryside of no particular significance. The 'Bally' prefix comes from the high incidence in usage in town names throughout Ireland, and comes from the Irish 'Baile', meaning home or town. Similar names include backobeyond (pronounced back oh beyond)

Ballygobackwards

Used in Ireland as a disparaging remark usually aimed at a particular town which is perceived as being antiquated or old-fashioned.

Bumfuck/Bumblefuck/BFE

Widely used to denote a backward, inbred community. Sometimes "West Bumfuck, Arkansas". The former term is also British slang for anal sex. Sometimes also referred to as "Bumblefuck, Egypt" or B.F.E.

Also used to describe a location of extreme remoteness or that is difficult to access. "Bumblefuck Nowhere"

East Jesus

Another name for a remote, rural or backward small town. The religious reference might imply a town with conservative or religious values or might simply be used for its mildly blasphemous humor.

Jerkwater Town

Yet another name for a remote, rural or backward small town.

The term's origin is in the late 19th century from when steam powered trains needed to refill their water tanks regularly. The trains did not stop at extremely small towns where only people were boarding. Instead they slowed down so that riders could hop on and off. Since the tanks still needed to be refilled, barrels of water were "jerked" aboard from platforms as the train passed.

This is also a possible etemology for the term "jerk" when applied to a person to indicate that they are dull or stupid.

Middle of Nowhere

Sometimes colloquially known as In the Sticks, In the Boonies, East Buttfuck, East Boofu, Back of Bourke Unlike Nowhere; these metasyntactic variables indicate extreme remoteness and suggest contempt.

Plumnelly

Another term for a remote location, Plumnelly is often used in the context of a border between two states or other areas: "plum out of Georgia and nelly out of Alabama." It can also be expressed as "plum out of town and nelly out of this world" to suggest that the location is so remote it has almost left the map entirely.

Podunk University

This term is sometimes a placeholder for a generic university.

Y.U. Bum University

This term is sometimes a placeholder for a less generic university. Pronounced like "Why you bum, you."

Waikikamukau

Traditional New Zealand placeholder for a small rural town. A plausible looking Māori place name, but which would be pronounced "Why kick a moo-cow?".

Wassamatta U.

Sometimes used for any university. Almost never used with more than "U." to represent "university". Less common than Y.U Bum U., or others. Used in the Rocky & Bullwinkle cartoon series.

Images

Test cards have been used as standard images as has Lenna.

Other languages

Other languages sometimes have their own metasyntactic variables. For example:

• Arabic: Fulan and Ellan for a person's name. Katha/Kaza and Matha/Maza for things.
• Bulgarian: eди какво for things (pronounced E-di kakVO), Горно Нанадолнище pronounced GOR-no na-na-DOL-ni-shte is comparable to the English Middle of Nowhere, Магадански институт for a university (popularized by a TV show)
• Chinese: Jia, Yi, Bing, Ding
• Danish: flaf, giraf, boing
• Dutch: aap, noot, mies, Piet, Jan, Kees
• English (Australian): duvelacky can be used for widget
• Estonian: kala (fish), kalatehas (fish factory), oxe (misspelled vomit)
• Filipino: kwan and ano (objects, sometimes locations), Pedro and Maria (people)
• Finnish: huu, haa, hahaa, hihii, hohoo
• French: toto, tata, titi, tutu, truc, machin, bidon
  • in Belgium: brol, prout
• German: muh, bla, blubb, schlurps, schnurz, dingens, gedöhnsrad, Lieschen Mueller, Hinz & Kunz, Otto Normalverbraucher, Hans Wurst, Max/Muster Mustermann
• Greek: koko, lala, malakia
  • Used by the Kangaroo Compiler Group: liroulirou
• Hebrew: Ploni (פלוני) or Ploni Almoni (פלוני אלמוני) as a person's name (see Ruth 4:1); Reuven (ראובן), Shim'on (שמעון), Levi (לוי), etc. for multiple people (after Jacob's sons)
• Hindi: Phalaan Phalaan
• Hungarian: Gipsz Jakab; alma, körte, barack, lófasz
• Indonesian: Anu, Fulan
• Italian: pippo, pluto, paperino
  • in Switzerland: Maria Bernasconi
• Japanese: hoge, hogehoge, moge, fuga, piyo, chomechome, nyoronyoro, naninani
• Malayalam: Appappan, mayav,Piley,purushu
• Norwegian: nalle
• Portuguese: bla, nha, la, patati, patata, coisa, treco, troço, negócio, Fulano, Sicrano and Beltrano (the last three as placeholders for persons' names), José da Silva(pretty common person name)
• Romanian: bubu, mumu, zeze
• Russian: Vasya Pupkin, Private Pupkin (Вася Пупкин, рядовой Пупкин), meaning abstract person, but generally a soldier or a programmer, Asya Pupkina (Ася Пупкина) - the female counterpart of Vasya, Muchosransk (Мухосранск) - a town in deep province, Derevnya Gadyukino (Деревня Гадюкино) - a village in the middle of nowhere
• Spanish: fulano, mengano, zutano (the three used to denote a supposed or fictional person), sultano (variant of the previously mentioned "zutano"), pedro, juan, diego (very common names), pepe (Jose), pp (phonetic equivalent to "pepe"), vaina, (vulgar), weá (Chilean vulgarism), cosa (thing; in Spanish, "cosa" can be anything, but usually refers to some physical object), pirola (has no meaning) pirolita (literally, "small pirola"; has no meaning)
• Swedish: apa (the Swedish word for monkey), bepa, cepa, depa (alphabetical generalizations of apa); bla, blahuj, ugg, ugga, blargh, gunk, tjo, bork; Kalle, Olle, Pelle, Nisse (the diminutives of Karl, Olof, Per and Nils respectively)
• Tamil: Kuppuswamy, Ramaswamy, Kuppan, Subban, Pulli Raja, Mannar & Company, All-in-all Azhagu Raja, Nadu theru Narayanan
• Turkish: filan, hede, hödö, zıvır, ıvır, ali, veli, deli, hasan - hüseyin
• Urdu: zaid name is used for examples.
• Yiddish: Plony (for a person, see Hebrew above); peh, meh, shmeh; Chaim Yankel for a person's name

It may also be interesting to note that lazy programmers who run out of nonsense words simply append numbers when they need more variables.

See also

• Placeholder name (Kadigan)
• Free variables and bound variables
• gadget
• widget
• Hello World
• Lorem Ipsum
• Fnord
• Alice and Bob

External links

• The Jargon File entry on Foo, and also the entry on Commonwealth Hackish for non-US English words such as "wombat".
• RFC 3092 - The IETF memo on Foo (note that this is an April Fool's Day RFC memo)
• Acme::MetaSyntactic A Perl module providing metasyntactic variable names. Updated weekly.
• The Foo Bar in Worcester, MA near WPI. Website does not explain name.