Editing Vertical bar (section)

==Encoding==

=== Solid vertical bar versus broken bar ===<!-- linked from an infobox in this article -->
[[Image:Dot printer ASCII0x7C+.png|320px|thumb|right|The code point 124 (7C [[hexadecimal]]) is occupied by a broken bar in a [[dot matrix printer]] of the late 1980s, which apparently lacks a solid vertical bar. See the [[:Image:Dot printer ASCII.png|full picture]].]]
Many early video terminals and [[dot-matrix printers]] rendered the vertical bar character as the [[allograph]] '''broken bar''' {{char|¦}}. This may have been to distinguish the character from the lower-case 'L' and the upper-case '{{serif|I}}' on these limited-resolution devices, and to make a vertical line of them look more like a horizontal line of dashes. It was also (briefly) part of the [[ASCII]] standard.

An initial draft for a 7-bit character set that was published by the X3.2 subcommittee for Coded Character Sets and Data Format on June 8, 1961, was the first to include the vertical bar in a standard set. The bar was intended to be used as the representation for the [[logical OR]] symbol.<ref name="evolutionchar">{{cite thesis |last=Fischer |first=Eric |date=2012 |title=The Evolution of Character Codes, 1874-1968 |publisher=Penn State University |citeseerx=10.1.1.96.678 |url=http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.96.678&rep=rep1&type=pdf |access-date=July 10, 2020}}</ref> A subsequent draft on May 12, 1966, places the vertical bar in column 7 alongside regional entry codepoints, and formed the basis for the original draft proposal used by the [[International Standards Organisation]].<ref name="evolutionchar"/> This draft received opposition from the [[IBM]] user group [[SHARE_(computing)|SHARE]], with its chairman, H. W. Nelson, writing a letter to the [[American Standards Association]] titled "The Proposed revised American Standard Code for Information Interchange does NOT meet the needs of computer programmers!"; in this letter, he argues that no characters within the international subset designated at columns 2-5 of the character set would be able to adequately represent logical OR and [[Negation|logical NOT]] in languages such as IBM's [[PL/I]] universally on all platforms.<ref>H. W. Nelson, letter to Thomas B. Steel, June 8, 1966, Honeywell Inc. X3.2 Standards Subcommittee Records, 1961-1969 (CBI 67), Charles Babbage Institute, University of Minnesota, Minneapolis, box 1, folder 23.</ref> As a compromise, a requirement was introduced where the [[exclamation mark]] (!) and [[circumflex]] (^) would display as logical OR (|) and logical NOT (¬) respectively in use cases such as programming, while outside of these use cases they would represent their original typographic symbols:
{{Cquote
| quote = "It may be desirable to employ distinctive styling to facilitate their use for specific purposes as, for example, to stylize the graphics in code positions 2/1 and 5/14 to those frequently associated with logical OR ({{Pipe}}) and logical NOT (¬) respectively."
| source = X3.2 document X3.2/475<ref>X3.2 document X3.2/475, December 13, 1966, Honeywell Inc. X3.2 Standards Subcommittee Records, 1961-1969 (CBI 67), Charles Babbage Institute, University of Minnesota, Minneapolis, box 1, folder 22.</ref>
}}

The original vertical bar encoded at 0x7C in the original May 12, 1966 draft was then broken as {{char|¦}}, so it could not be confused with the unbroken logical OR. In the 1967 revision of ASCII, along with the equivalent ISO 464 code published the same year, the code point was defined to be a broken vertical bar, and the exclamation mark character was allowed to be rendered as a solid vertical bar.<ref name="Salste_2016" /><ref name="Korpela">{{cite web |title=Character histories - notes on some Ascii code positions |author-first=Jukka |author-last=Korpela |url=http://jkorpela.fi/latin1/ascii-hist.html |access-date=2020-05-31 |url-status=live |archive-url=https://web.archive.org/web/20200311174647/http://jkorpela.fi/latin1/ascii-hist.html |archive-date=2020-03-11}}</ref> However, the 1977 revision (ANSI X.3-1977) undid the changes made in the 1967 revision, enforcing that the circumflex could no longer be stylised as a logical NOT symbol, the exclamation mark likewise no longer allowing stylisation as a vertical bar, and defining the code point originally set to the broken bar as a solid vertical bar instead;<ref name="Salste_2016">{{cite web |title=7-bit character sets: Revisions of ASCII |author-first=Tuomas |author-last=Salste |publisher=Aivosto Oy |date=January 2016 |id={{URN|nbn|fi-fe201201011004}} |url=http://www.aivosto.com/vbtips/charsets-7bit.html#body |access-date=2016-06-13 |url-status=live |archive-url=https://web.archive.org/web/20160613145224/http://www.aivosto.com/vbtips/charsets-7bit.html#body |archive-date=2016-06-13}}</ref> the same changes were also reverted in ISO 646-1973 published four years prior.

Some variants of [[EBCDIC]] included both versions of the character as different code points. The broad implementation of the [[extended ASCII]] [[ISO/IEC 8859]] series in the 1990s also made a distinction between the two forms. This was preserved in Unicode as a separate character at {{unichar|00A6}} (the term "parted rule" is used sometimes in Unicode documentation). Some fonts draw the characters the same (both are solid vertical bars, or both are broken vertical bars).<ref>{{cite web|url=http://www.jimprice.com/jim-asc.shtml#extended|title=ASCII Chart: IBM PC Extended ASCII Display Characters|author=Jim Price|date=2010-05-24|access-date=2012-02-23}}</ref>{{failed verification|date=July 2020}}<!-- I saw personally the logical OR operator in C rendered as ЭЭ in KOI-7 environment, but it is a bit off-topic here. --Incnis Mrsi -->

The broken bar does not appear to have any clearly identified uses distinct from those of the vertical bar.<ref>{{cite web|url=https://jkorpela.fi/latin1/3.html#A6|title=Detailed descriptions of the characters|date=2006-09-20|author=Jukka "Yucca" Korpela|access-date=2012-02-23}}</ref> In non-computing use — for example in mathematics, physics and general typography — the broken bar is not an acceptable substitute for the vertical bar. In some dictionaries, the broken bar is used to mark stress that may be either primary or secondary: {{IPA|[¦ba]}} covers the pronunciations {{IPA|[ˈba]}} and {{IPA|[ˌba]}}.<ref>For example, {{MW|Balearic}}.</ref>

===Unicode code points===
These glyphs are encoded in Unicode as follows:
* {{unichar|007C|Vertical line|html=}} (single vertical line)
* {{unichar|00A6|Broken bar|html=}} (single broken line)
* {{unichar|2016|Double vertical line|html=}} (double vertical line ( <math>\|</math> ): used in pairs to indicate [[Norm (mathematics)|norm]])
* {{unichar|FF5C|Fullwidth vertical line|html=}} ([[Halfwidth and fullwidth forms|Fullwidth form]])
* {{unichar|FFE4|Fullwidth broken bar|html=}}
* {{unichar|2225|Parallel to|html=| nlink=Parallel (geometry)}}
* {{unichar|01C0|Latin letter dental click| html= |nlink=Click consonant}}
* {{unichar|01C1|Latin letter lateral click| html= |nlink=Click consonant}}
* {{unichar|2223|divides| html= |nlink=Divisor}}
* {{unichar|2502|Box drawings light vertical|nlink=Box-drawing characters|html=}} (and various other box drawing characters in the range U+2500 to U+257F)
* {{unichar|2758|Light vertical bar}}
* {{unichar|0964|Devanagari Danda|nlink=Danda|html=}}
* {{unichar|0965|Devanagari double Danda|nlink=Danda|html=}}

===Code pages and other historical encodings===
{| class="wikitable collapsible mw-collapsed"
!Code pages, ASCII, ISO/IEC, EBCDIC, Shift-JIS, etc.
!Vertical bar (<code><nowiki>|</nowiki></code>)
!Broken bar (<code>¦</code>)
|-
|[[ASCII]],<br />[[CP437]], [[CP667]], [[CP720]], [[CP737]], [[CP790]], [[CP819]], [[CP852]], [[CP855]], [[CP860]], [[CP861]], [[CP862]], [[CP865]], [[CP866]], [[CP867]], [[CP869]], [[CP872]], [[CP895]], [[Code page 932 (IBM)|CP932]], [[CP991]]
|rowspan=7|124 (7C[[hexadecimal|h]])
|none
|-
|[[CP775]]
|167 (A7h)
|-
|[[CP850]], [[CP857]], [[CP858]]
|221 (DDh)
|-
|[[CP863]]
|160 (A0h)
|-
|[[CP864]]
|219 (DBh)
|-
|[[ISO/IEC 8859-1]], [[ISO/IEC 8859-7|-7]], [[ISO/IEC 8859-8|-8]], [[ISO/IEC 8859-9|-9]], [[ISO/IEC 8859-13|-13]],<br />[[CP1250]], [[CP1251]], [[CP1252]], [[CP1253]], [[CP1254]], [[CP1255]], [[CP1256]], [[CP1257]], [[CP1258]]
|166 (A6h)
|-
|[[ISO/IEC 8859-2]], [[ISO/IEC 8859-3|-3]], [[ISO/IEC 8859-4|-4]], [[ISO/IEC 8859-5|-5]], [[ISO/IEC 8859-6|-6]], [[ISO/IEC 8859-10|-10]], [[ISO/IEC 8859-11|-11]], [[ISO/IEC 8859-14|-14]], [[ISO/IEC 8859-15|-15]], [[ISO/IEC 8859-16|-16]]
|none
|-
|[[EBCDIC]] CCSID 37
|79 (4Fh)
|rowspan=2|106 (6Ah)
|-
|[[EBCDIC]] CCSID 500
|187 (BBh)
|-
|[[JIS X 0208]], [[JIS X 0213]]
|[[Kuten|Men-ku-ten]] 1-01-35 (7-bit: 2143h; {{nobr|[[Shift JIS]]}}: 8162h; [[EUC-JP|EUC]]: A1C3h){{efn|The Shift JIS and EUC encoded forms also include the ASCII vertical bar in its usual encoding (see [[halfwidth and fullwidth forms]]). The same applies when the 7-bit form is used as part of [[ISO-2022-JP]] (allowing switching to and from ASCII).}}
|none
|}