Laqme at 23:47, 27 May 2024

2024-05-27T23:47:42Z

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	'''Unicode''' is a ~~system~~ that assigns numeric codes to writing systems from all over the world.		'''Unicode''' is a text encoding standard that assigns numeric codes to writing systems from all over the world.

	This page compiles some facts about Unicode that Toaqists may find useful to know.		This page compiles some facts about Unicode that Toaqists may find useful to know.

Laqme: Initial article

2024-05-27T23:42:47Z

Initial article

New page

'''Unicode''' is a system that assigns numeric codes to writing systems from all over the world.

This page compiles some facts about Unicode that Toaqists may find useful to know.

== Unicode vs. UTF-8 ==
Unicode, the '''standard''', dictates (for example) that the character {{t|ꝡ}} is represented by the number 42849, or A761 in hexadecimal.

These "codepoint numbers" are usually written as U+ followed by the hexadecimal number: U+A761.

UTF-8, an '''encoding''', dictates how to encode that number across bytes in a file: it says U+A761 is <code>ea 9d a1</code>.

There are other encodings of Unicode, but they are not as commonly used. For example, in UTF-16, the encoding of U+A761 is simply <code>a7 61</code>.

== Combining characters and normalization ==
A letter with a diacritic like {{t|é}} can be represented as a '''precomposed''' form (<code>é</code> U+00E9 {{small caps|latin small letter e with acute}}) or as a sequence of a base letter and combining characters (<code>e</code> U+0065 {{small caps|latin small letter e}} and <code>◌́</code> U+0301 {{small caps|combining acute accent}}).

Unicode text may be '''normalized''' to smooth over these differences: either by precomposing everything as much as possible (normalization form C or NFC) or by decomposing everything into combining characters (normalization form D or NFD).

Normalization also pins down the ''order'' of combining characters. Underdots come before hats. The string <code>é + underdot</code> has NFC <code>ẹ + acute</code> and NFD <code>e + underdot + acute</code>.

=== Dotless {{t|ı}} and normalization ===
The letter {{t|í}} decomposes into <code>i + acute</code>, not <code>ı + acute</code>. Placing diacritics on a dotless <code>ı</code> may produce wrong-looking results. Compare:

{| class="wikitable"
! Letter
! NFC
! NFD
|-
| style="text-align:center;" | {{t|ı}} || <code>ı</code> || <code>ı</code>
|-
| style="text-align:center;" | {{t|î}} || <code>î</code> || <code>i + circumflex</code>
|-
| style="text-align:center;" | {{t|ı̣}} || <code>ı + underdot</code> || <code>ı + underdot</code>
|-
| style="text-align:center;" | {{t|ị̂}} || <code>ị + circumflex</code> || <code>i + underdot + circumflex</code>
|}

=== Precomposed tone–underdot combos ===
Not all Toaq tone–underdot combos have precomposed characters. This table shows precomposed characters in green and NFC forms in red:

{| class="wikitable toaq" style="text-align: center;"
!
! {{done|1}}
! {{done|2}}
! {{done|3}}
! {{done|4}}
|-
! a
| style="background-color: lightgreen;" | ạ
| style="background-color: lightpink; | '''ạ́'''
| style="background-color: lightpink; | '''ạ̈'''
| style="background-color: lightgreen;" | ậ
|-
! u
| style="background-color: lightgreen;" | ụ
| style="background-color: lightpink; | '''ụ́'''
| style="background-color: lightpink; | '''ụ̈'''
| style="background-color: lightpink; | '''ụ̂'''
|-
! ı
| style="background-color: lightpink; | '''ı̣'''
| style="background-color: lightpink; | '''ị́'''
| style="background-color: lightpink; | '''ị̈'''
| style="background-color: lightpink; | '''ị̂'''
|-
! o
| style="background-color: lightgreen;" | ọ
| style="background-color: lightpink; | '''ọ́'''
| style="background-color: lightpink; | '''ọ̈'''
| style="background-color: lightgreen;" | ộ
|-
! e
| style="background-color: lightgreen;" | ẹ
| style="background-color: lightpink; | '''ẹ́'''
| style="background-color: lightpink; | '''ẹ̈'''
| style="background-color: lightgreen;" | ệ
|}

Paradoxically, depending on the font and operating system, the "abnormal" forms (like <code>é + underdot</code>) may show up more correctly. They are demonstrated in the table below:

{| class="wikitable toaq" style="text-align: center;"
!
! {{done|1}}
! {{done|2}}
! {{done|3}}
! {{done|4}}
|-
! a
| ạ || ạ́ || ạ̈ || ậ
|-
! u
| ụ || ụ́ || ụ̈ || ụ̂
|-
! ı
| ı̣ || ị́ || ị̈ || ị̂
|-
! o
| ọ || ọ́ || ọ̈ || ộ
|-
! e
| ẹ || ẹ́ || ẹ̈ || ệ
|}

(MediaWiki [https://www.mediawiki.org/wiki/Unicode_normalization_considerations normalizes page contents], meaning that the above table has had to use HTML entities to get the desired effect (e.g. <code>í&#x323;</code> for {{t|ị́}}). [[Template:T]] will do this for you.)

== See also ==
* [[Latin writing system]]
* [[Input methods]]

Unicode - Revision history

Laqme at 23:47, 27 May 2024

Laqme: Initial article