Colon (punctuation)

Source: Wikipedia, the free encyclopedia.
:
Colon
U+003A : COLON (:)

The colon, :, is a

formal letter writing.[1]

History

In

prosody, the term κῶλον (kôlon, lit. 'limb, member of a body') did not refer to punctuation, but to a member or section of a complete thought or passage; see also Colon (rhetoric). From this usage, in palaeography, a colon is a clause or group of clauses written as a line in a manuscript.[5]

In the 3rd century BC,

Punctuation in Ancient Greek
.)

In 1589, in The Arte of English Poesie, the English term colon and the corresponding punctuation mark : is attested:[7][a]

For these respectes the auncient reformers of language, inuented, three maner of pauses [...] The shortest pause or intermission they called comma [...] The second they called colon, not a peece but as it were a member for his larger length, because it occupied twise as much time as the comma. The third they called periodus, [...]

In 1622, in

dog's bollocks, was once common in British English; though this usage is now discouraged.[9][10][11]

As late as the 18th century, John Mason related the appropriateness of a colon to the length of the pause taken when reading the text aloud, but silent reading eventually replaced this with other considerations.[12]

Usage in English

In modern English usage, a complete sentence precedes a colon, while a list, description, explanation, or definition follows it. The elements which follow the colon may or may not be a complete sentence: since the colon is preceded by a sentence, it is a complete sentence whether what follows the colon is another sentence or not. While it is acceptable to capitalise the first letter after the colon in American English, it is not the case in British English, except where a proper noun immediately follows a colon.[13]

Colon used before list
Daequan was so hungry that he ate everything in the house: chips, cold pizza, pretzels and dip, hot dogs, peanut butter, and candy.
Colon used before a description
Bertha is so desperate that she'll date anyone, even William: he's uglier than a squashed toad on the highway, and that's on his good days.
Colon before definition
For years while I was reading Shakespeare's Othello and criticism on it, I had to constantly look up the word "egregious" since the villain uses that word: outstandingly bad or shocking.
Colon before explanation
I guess I can say I had a rough weekend: I had chest pain and spent all Saturday and Sunday in the emergency room.

Some writers use fragments (incomplete sentences) before a colon for emphasis or stylistic preferences (to show a character's voice in literature), as in this example:

Dinner: chips and juice. What a well-rounded diet I have.

appositive, or a quotation, and it can be used between independent clauses if the second summarizes or explains the first. In non-literary or non-expository uses, one may use a colon after the salutation in a formal letter, to indicate hours and minutes, to show proportions, between a title and subtitle, and between city and publisher in bibliographic entries.[14]

Luca Serianni, an Italian scholar who helped to define and develop the colon as a punctuation mark, identified four punctuational modes for it: syntactical-deductive, syntactical-descriptive, appositive, and segmental.[15]

Syntactical-deductive

The colon introduces the logical consequence, or effect, of a fact stated before.

There was only one possible explanation: the train had never arrived.

Syntactical-descriptive

In this sense the colon introduces a description; in particular, it makes explicit the elements of a set.

I have three sisters: Daphne, Rose, and Suzanne.

Syntactical-descriptive colons may separate the numbers indicating hours, minutes, and seconds in abbreviated measures of time.[16]

The concert begins at 21:45.
The rocket launched at 09:15:05.

point
for this purpose:

The programme will begin at 8.00 pm.
You will need to arrive by 14.30.[17][18]

A colon is also used in the descriptive location of a book verse if the book is divided into verses, such as in the Bible or the Quran:

"Isaiah 42:8"
"Deuteronomy 32:39"
"Quran 10:5"

Appositive

Luruns could not speak: he was drunk.[19]

An appositive colon also separates the subtitle of a work from its principal title. (In effect, the example given above illustrates an appositive use of the colon as an abbreviation for the conjunction "because".) Dillon has noted the impact of colons on scholarly articles,[20][21] but the reliability of colons as a predictor of quality or impact has also been challenged.[22][23] In titles, neither needs to be a complete sentence as titles do not represent expository writing:

Star Wars Episode VI: Return of the Jedi

Segmental

Like a dash or quotation mark, a segmental colon introduces speech. The segmental function was once a common means of indicating an unmarked quotation on the same line. The following example is from the grammar book The King's English:

Benjamin Franklin proclaimed the virtue of frugality: A penny saved is a penny earned.

This form is still used in British industry-standard templates for written performance dialogues, such as in a play.[24] The colon indicates that the words following an character's name are spoken by that character.

Patient: Doctor, I feel like a pair of curtains.
Doctor: Pull yourself together!

The uniform visual pattern of <character_nametag : character_spoken_lines> placement on a script page assists an actor in scanning for the lines of their assigned character during rehearsal, especially if a script is undergoing rewrites between rehearsals.

Use of capitals

Use of capitalization or lower-case after a colon varies. In British English, and in most Commonwealth countries, the word following the colon is in lower case unless it is normally capitalized for some other reason, as with proper nouns and acronyms. British English also capitalizes a new sentence introduced by a colon's segmental use.[citation needed]

American English permits writers to similarly capitalize the first word of any independent clause following a colon. This follows the guidelines of some modern American style guides, including those published by the Associated Press and the Modern Language Association. The Chicago Manual of Style, however, requires capitalization only when the colon introduces a direct quotation, a direct question, or two or more complete sentences.[25][failed verification]

In many European languages, the colon is usually followed by a lower-case letter unless the upper case is required for other reasons, as with British English. German usage requires capitalization of independent clauses following a colon.[26] Dutch further capitalizes the first word of any quotation following a colon, even if it is not a complete sentence on its own.[27]

Spacing and parentheses

In print, a thin space was traditionally placed before a colon and a thick space after it. In modern

English-language printing, no space is placed before a colon and a single space is placed after it.[28][29] In French-language
typing and printing, the traditional rules are preserved.

One or two spaces may be and have been used after a colon. The older convention (designed to be used by monospaced fonts) was to use two spaces after a colon.[30]

In modern typography, a colon will be placed outside the closing

parenthesis introducing a list. In very early English typography, it could be placed inside, as seen in Roger Williams' 1643 book about the Native American languages of New England.[31]

Usage in other languages

Suffix separator

In

initialism, a special symbol, or a digit (e.g., Finnish USA:n and Swedish USA:s for the genitive case of "USA", Finnish %:ssa for the inessive case of "%", or Finnish 20:een for the illative case
of "20").

Abbreviation mark

Written Swedish uses colons in

Svenska k:a (Svenska kyrkan), the Evangelical Lutheran national Church of Sweden. This can even occur in people's names, for example Antonia Ax:son Johnson (Ax:son for Axelson). Early Modern English texts also used colons to mark abbreviations.[32][33]

Word separator

15th century Bible text in Ge'ez script showing colons between the words.

In

word separator
.

Historically, a colon-like mark was used as a word separator in Old Turkic script.

End of sentence or verse

In Armenian, a colon indicates the end of a sentence, similar to a Latin full stop or period.

In liturgical Hebrew, the sof pasuq is used in some writings such as prayer books to signal the end of a verse.

Score divider

In German, and sometimes in English, a colon divides the scores of opponents in sports and games. A result of 149–0 would be written as 149 : 0 in German.

Mathematics and logic

The colon is used in mathematics, cartography, model building, and other fields—in this context it denotes a ratio or a scale, as in 3∶1 (pronounced "three to one").[1]

When a ratio is reduced to a simpler form, such as 10∶15 to 2∶3, this may be expressed with a double colon as 10∶15∶∶2∶3; this would be read "10 is to 15 as 2 is to 3". This form is also used in tests of logic where the question of "Dog is to Puppy as Cat is to _____?" can be expressed as "Dog∶Puppy∶∶Cat∶_____". For these usages the proper Unicode symbol is (U+2236 RATIO) that is a little higher up than the normal colon. Compare 2∶3 (ratio colon) with 2:3 (normal colon).

In some languages (e.g. German, Russian, and French), the colon is the commonly used sign for division (instead of ÷). (See also Division sign and Division (mathematics) § Notation.)

The notation |G : H| may also denote the index of a subgroup.

The notation ƒ : X → Y indicates that f is a function with domain X and codomain Y.

The combination with an equal sign () is used for definitions.

In mathematical logic, when using set-builder notation for describing the characterizing property of a set, it is used as an alternative to a vertical bar (which is the ISO 31-11 standard), to mean "such that". Example:

(S is the set of all x in (the real numbers) such that x is strictly greater than 1 and strictly smaller than 3)

In older literature on mathematical logic, it is used to indicate how expressions should be bracketed (see Glossary of Principia Mathematica).

In type theory and programming language theory, the colon sign after a term is used to indicate its type, sometimes as a replacement to the "∈" symbol. Example:

.

A colon is also sometimes used to indicate a tensor contraction involving two indices, and a double colon (::) for a contraction over four indices.

A colon is also used to denote a

for this purpose).

Computing

The character was on early typewriters and therefore appeared in most text encodings, such as Baudot code and EBCDIC. It was placed at code 58 in ASCII and from there inherited into Unicode. Unicode also defines several related characters:

  • U+003A : COLON
  • U+02D0 ː MODIFIER LETTER TRIANGULAR COLON, used in IPA.[34]
  • U+10781 𐞁 MODIFIER LETTER SUPERSCRIPT TRIANGULAR COLON, IPA modifier-letter.[35]
  • U+02D1 ˑ MODIFIER LETTER HALF TRIANGULAR COLON, used in IPA.
  • U+10782 𐞂 MODIFIER LETTER SUPERSCRIPT HALF TRIANGULAR COLON, IPA modifier-letter.[35]
  • U+02F8 ˸ MODIFIER LETTER RAISED COLON, used by Uralic Phonetic Alphabet.[36]
  • U+05C3 ׃ HEBREW PUNCTUATION SOF PASUQ, compatible with right-to-left text.
  • U+2236 RATIO, for mathematical usage.
  • U+2254 COLON EQUALS, for use in pretty-printing programming languages.
  • U+2255 EQUALS COLON[37]
  • U+2360 APL FUNCTIONAL SYMBOL QUAD COLON
  • U+2982 Z NOTATION TYPE COLON
  • U+2A74 DOUBLE COLON EQUAL
  • U+2AF6 TRIPLE COLON OPERATOR
  • U+A789 MODIFIER LETTER COLON, see
    reserved character
    .
  • U+FE13 PRESENTATION FORM FOR VERTICAL COLON, compatibility character for the Chinese Standard GB 18030.
  • U+FF1A FULLWIDTH COLON, for compatibility with halfwidth and fullwidth fonts.
  • U+FE55 SMALL COLON, compatibility character for the Chinese National Standard CNS 11643.

Programming languages

A number of programming languages, most notably ALGOL, Pascal and Ada, use a colon and equals sign := as the assignment operator, to distinguish it from a single equals = which is an equality test (C instead used a single equals as assignment, and a double equals == as the equality test).[38][39]

Many languages including C and Java use the colon to indicate the text before it is a label, such as a target for a goto or an introduction to a case in a switch statement.[40]: 131 [41] In a related use, Python uses a colon to separate a control statement (the clause header) from the block of statements it controls (the suite):[42]

if test(x):
    print("test(x) is true!")
else:
    print("test(x) is not true...")

In a number of languages, including JavaScript, colons are used to define name–value pairs in a dictionary or object.[43]: 96–100  This is also used by data formats such as JSON.[44] Some other languages use an equals sign.

var obj = {
    name: "Charles",
    age: 18,
}

The colon is used as part of the

?: conditional operator in C and many other languages.[40]
: 90 

class member access.[45] Most other languages use a period but C++ had to use this for compatibility with C. Another language using colons for scope resolution is Erlang, which uses a single colon.[46]

In BASIC, it is used as a separator between the statements or instructions in a single line. Most other languages use a semicolon, but BASIC had used semicolon to separate items in print statements.[47]

In Forth, a colon precedes definition of a new word.[48]

list:[49]

"child" : ["woman", "man"] -- equals ["child","woman","man"]

while a double colon :: is read as "has type of" (compare scope resolution operator):[50]

("text", False) :: ([Char], Bool)

The ML languages (such as Standard ML) have the above reversed, where the double colon (::) is used to add an element to the front of a list; and the single colon (:) is used for type guards.[51]: 20, 70 

MATLAB uses the colon as a binary operator that generates vectors, as well as to select particular portions of existing matrices.

APL uses the colon:

  • to introduce a control structure element. In this usage it must be the first non-blank character of the line.[52]: 64 
  • after a label name that will be the target of a :goto or a right-pointing arrow (Note: this style of programming is deprecated and programmers are encouraged to use control structures instead).[52]: 64 
  • to separate a guard (Boolean expression) from its expression in a dynamic function.[52]: 111  Two colons are used for an Error guard (one or more error numbers).[52]: 115 
  • Colon + space are used in class definitions to indicate inheritance.[52]: 135 
  • ⍠ (a colon in a box) is used by APL for its variant operator.[52]: 340 

The colon is also used in many operating systems commands.[53]

In the esoteric programming language INTERCAL, the colon is called "two-spot" and is used to identify a 32-bit variable—distinct from a spot (.) which identifies a 16-bit variable.[54]: 3 

Addresses

Internet URLs use the colon to separate the protocol (such as http:) from the hostname or IP address.[55]

In an

port number from the hostname or IP address.[55]

In

BSD-based macOS
due to code swapping the slash and colon to try to preserve this usage. In most systems it is often difficult to put a colon in a filename as the shell interprets it for other purposes.

Text markup

It is often used as a single post-fix delimiter, signifying a token keyword had immediately preceded it or the transition from one mode of character string interpretation to another related mode. Some applications, such as the widely used MediaWiki, utilize the colon as both a pre-fix and post-fix delimiter.

In

wiki markup
, the colon is often used to indent text. Common usage includes separating or marking comments in a discussion as replies, or to distinguish certain parts of a text.

Markup Renders as
Normal text.
:Indented text by the means of a colon.
::The gap increases with colon number.

Normal text.

Indented text by the means of a colon.
The gap increases with colon number.

In human-readable text messages, a colon, or multiple colons, is sometimes used to denote an action (similar to how asterisks are used)[original research?] or to emote (for example, in vBulletin). In the action denotation usage it has the inverse function of quotation marks, denoting actions where unmarked text is assumed to be dialogue. For example:

Tom: Pluto is so small; it should not be considered a planet. It is tiny!
Mark: Oh really? ::drops Pluto on Tom's head:: Still think it's small now?

Colons may also be used for sounds, e.g., ::click::, though sounds can also be denoted by asterisks or other punctuation marks.

Colons can also be used to represent eyes in emoticons.

See also

Notes

  1. ^ The work was published anonymously and attributed to George Puttenham in reprints.[7]

References

  1. ^ a b c d "Colon". The Punctuation Guide. Archived from the original on 11 November 2020. Retrieved 22 November 2020.
  2. ^ "punctuation". The Economist Style Guide. Archived from the original on 2021-05-23. Retrieved 2021-05-23.
  3. ^ International Committee of Medical Journal Editors (ICMJE) Uniform Requirements for Manuscripts Submitted to Biomedical Journals: Sample References, United States National Library of Medicine, archived from the original on 2020-02-17, retrieved 2013-03-01
  4. ^ "How to Cite the Bible*. Guide for Four Citation Styles: MLA, APA, SBL, CHICAGO" (PDF). jbu.edu. John Brown University. Archived from the original (PDF) on 2021-09-28. Retrieved 2021-05-23.
  5. ^ Oxford English Dictionary, 1st ed. "colon, n.²" Oxford University Press (Oxford), 1891.
  6. ^ Nicolas, Nick. "Greek Unicode Issues: Punctuation Archived 6 August 2012 at archive.today". 2005. Accessed 7 October 2014.
  7. ^ a b Arber, Edward, ed. (1869). The Arte of English Poesie: 1589. London: Alex. Murray & Son. p. 88. Archived from the original on 2022-10-26. Retrieved 2022-10-26.
  8. .
  9. ^ Dean, Paul (25 April 2008). "Extreme Type Terminology Part 4: Numerals and Punctuation". I Love Typography. Archived from the original on 19 November 2014. Retrieved 28 November 2014.
  10. ^ Martens, Nick (20 January 2010). "The Secret History of Typography in the Oxford English Dictionary". The Bygone Bureau. Archived from the original on 22 November 2014. Retrieved 28 November 2014.
  11. ^ Trask, Larry. "The Colon". University of Sussex. Archived from the original on 16 January 2018. Retrieved 28 November 2014.
  12. ^ John Mason's work, An Essay on Elocution (1748), notes that "A Comma Stops the Voice while we may privately tell one, a Semi Colon two; a Colon three: and a Period four."
  13. ^ "Colons: How to Use Them". The MLA Style Center. 2017-09-20. Archived from the original on 2020-08-10. Retrieved 2020-08-17.
  14. .
  15. .
  16. ^ Data elements and interchange formats – Information interchange – Representation of dates and times.
  17. ^ Trask, Larry (1997). "The Colon". Guide to Punctuation. Archived from the original on 16 January 2018. Retrieved 26 July 2019.
  18. .
  19. ^ Example quoted in An Educational Companion to Eats, Shoots & Leaves by Lynne Truss
  20. .
  21. .
  22. ^ Townsend, Michael A.R. (1983). "Titular Colonicity and Scholarship: New Zealand Research and Scholarly Impact" (PDF). New Zealand Journal of Psychology. 12: 41–43. Archived (PDF) from the original on 2017-04-09. Retrieved 2017-04-20.
  23. .
  24. ^ "Playscript template". Archived from the original on 2023-03-13. Retrieved 2023-03-13.
  25. ^ "Chicago Style Q&A: Capitalization". Chicagomanualofstyle.org. Archived from the original on 15 October 2012. Retrieved 8 November 2011.
  26. ^ Duden Newsletter vom 24.08.2001
  27. ^ "Hoofdletter na dubbele punt". taaladvies.net. Archived from the original on 26 October 2011. Retrieved 8 November 2011.
  28. ^ DeRespinis, Francis; Hayward, Peter; Jenkins, Jana; Laird, Amy; McDonald, Leslie; Radzinski, Eric (2012). The IBM Style Guide: Conventions for Writers and Editors. Boston: IBM Press. p. 43.
  29. ^ Gibaldi, Joseph (2008). MLA Style Manual and Guide to Scholarly Publishing. New York: Modern Language Association of America. p. 91.
  30. ^ Paterson, Derek (19 November 2009). "How many spaces after a colon?". Absolute Write forums. Post 4. Archived from the original on 27 September 2013. Retrieved 4 November 2012. Back in the typewriter day, when fading ink ribbons could result in commas being mistaken for periods and vice versa, typists were taught to insert 2 spaces after the period to differentiate between the two. The same happened with colons and semicolons: 2 spaces were left after a colon; 1 space after a semicolon.
  31. ^ "A key into the language of America". 1643.
  32. .
  33. . In the medieval and early modern eras, [...] the colon and raised dot [...] signal a contracted word [...].
  34. ^ "The International Phonetic Alphabet". Weston Ruter. 2005. Archived from the original on 29 July 2012. Retrieved 27 October 2011.
  35. ^ a b Miller, Kirk; Ashby, Michael (2020-11-08). "L2/20-252R: Unicode request for IPA modifier-letters (a), pulmonic" (PDF). Archived (PDF) from the original on 2021-07-30. Retrieved 2022-09-21.
  36. ^ Everson, Michael; et al. (20 March 2002). "L2/02-141: Uralic Phonetic Alphabet characters for the UCS" (PDF). Archived (PDF) from the original on 19 February 2018.
  37. ^ Whistler, Ken; Freytag, Asmus (19 April 2000). "L2/00-119: Encoding Additional Mathematical Symbols in Unicode" (PDF). Archived (PDF) from the original on 19 February 2018.
  38. ^ "Becomes". Free Pascal and Lazarus Wiki. 4 February 2021. Archived from the original on 2 March 2022.
  39. ^ "Ada Reference Manual - 5.2 Assignment Statements". Ada Conformity Assessment Authority. 2012. Archived from the original on 20 May 2020.
  40. ^ a b ISO/IEC JTC1/SC22/WG14 (7 September 2007). "ISO/IEC 9899:TC3 — Programming languages — C" (PDF). Archived (PDF) from the original on 16 April 2020.{{cite web}}: CS1 maint: numeric names: authors list (link)
  41. ^ "The Java® Language Specification - Chapter 14. Blocks, Statements, and Patterns". Oracle Help Center. Oracle. 23 February 2022. Archived from the original on 8 June 2022.
  42. ^ "The Python Language Reference - 8. Compound statements". Python Software Foundation. 22 January 2016. Archived from the original on 26 January 2016.
  43. ^ ECMA TC39 (June 2022). ECMA-262 (PDF) (13th ed.). Ecma International. Archived (PDF) from the original on 4 July 2022.{{cite book}}: CS1 maint: numeric names: authors list (link)
  44. ISSN 2070-1721. STD 90. RFC 8259. Internet Standard 90. Obsoletes RFC 7159
    .
  45. ^ "Identifiers". C++ Reference. 16 June 2022. Archived from the original on 22 July 2022. Retrieved 28 July 2022.{{cite web}}: CS1 maint: bot: original URL status unknown (link)
  46. ^ "Erlang Reference Manual - Expressions". Erlang. Ericsson. 15 July 2022. Archived from the original on 21 July 2022. Retrieved 28 July 2022.{{cite web}}: CS1 maint: bot: original URL status unknown (link)
  47. ^ "Special Characters in Code (Visual Basic)". Microsoft Docs. Microsoft. 15 September 2021. Archived from the original on 11 April 2022.
  48. ^ "- CORE - Glossary". Forth Standard. Forth-Standard-Committee. Archived from the original on 17 November 2015.
  49. ^ O'Sullivan, Bryan; Stewart, Don; Goerzen, John. "Getting Started". Real World Haskell. Archived from the original on 10 July 2012. Retrieved 8 November 2011.
  50. ^ Lipovača, Miran. "Types and Typeclasses". Learn You a Haskell for Great Good!. Archived from the original on 10 July 2012. Retrieved 8 November 2011.
  51. (PDF) from the original on 30 April 2020.
  52. ^ a b c d e f "Dyalog APL Language Reference Manual" (PDF). Dyalog Limited. April 2011. Archived (PDF) from the original on 4 March 2016. Retrieved 14 February 2012.
  53. ^ "colon - null utility". IEEE Std 1003.1-2017. The Open Group. 2018. Archived from the original on 17 October 2018.
  54. ^ Woods, Donald R.; Lyon, James M. (1973). "INTERCAL reference manual". Archived from the original (PS) on 2011-07-16. Retrieved 2012-03-10.
  55. ^
    doi:10.17487/RFC3986. STD 66. RFC 3986. Internet Standard 66. Obsoletes RFC 2732, 2396 and 1808. Updated by RFC 6874, 7320 and 8820. Updates RFC 1738
    .
  56. doi:10.17487/RFC4291. RFC 4291. Draft Standard. Obsoletes RFC 3513. Updated by RFC 5952, 6052, 7136, 7346, 7371 and 8064
    .
  57. ^ "[MS-FSCC]: 2.1.5 Pathname". Microsoft Docs. Microsoft. 24 August 2020. Archived from the original on 22 October 2020.

External links