Arabic Presentation Forms-B

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Arabic Presentation Forms-B
RangeU+FE70..U+FEFF
(144 code points)
PlaneBMP
ScriptsArabic (140 char.)
Common (1 char.)
Symbol setscontextual and isolate forms of Arabic letters and points
Assigned141 code points
Unused3 reserved code points
Unicode version history
1.0.0 (1991)140 (+140)
3.2 (2002)141 (+1)
Unicode documentation
Code chart ∣ Web page
Note: [1][2]
The characters in this block were re-ordered in Unicode 1.0.1, in the process of merging with ISO/IEC 10646.[3]

Arabic Presentation Forms-B is a Unicode block encoding spacing forms of Arabic diacritics, and contextual letter forms. The special codepoint ZWNBSP (zero width no-break space) is also here, which is only meant for a byte order mark (that may precede text, Arabic or not, or be absent) The byte-order mark is very useful in detecting endianness in UTF-16, because when it is at the start of UTF-16 data and the interpreter reads the first character as the noncharacter U+FFFE, the file is clearly interpreted with the wrong endianness.[note 1] The block name in Unicode 1.0 was Basic Glyphs for Arabic Language;[5] its characters were re-ordered in the process of merging with ISO 10646 in Unicode 1.0.1 and 1.1.[3]

The presentation forms are present only for compatibility with older standards, and are not currently needed for coding text.[6]

Block

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Arabic Presentation Forms-B[1][2]
Official Unicode Consortium code chart (PDF)
  0 1 2 3 4 5 6 7 8 9 A B C D E F
U+FE7x ﹿ
U+FE8x
U+FE9x
U+FEAx
U+FEBx ﺿ
U+FECx
U+FEDx
U+FEEx
U+FEFx ZW
NBSP
Notes
1.^ As of Unicode version 17.0
2.^ Grey areas indicate non-assigned code points

History

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The following Unicode-related documents record the purpose and process of defining specific characters in the Arabic Presentation Forms-B block:

References

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  1. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  2. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  3. ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  4. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  5. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  6. ^ The Unicode Consortium. The Unicode Standard, Version 6.0.0, (Mountain View, CA: The Unicode Consortium, 2011. Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).), Chapter 8

Notes

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  1. ^ As the name suggests, it was also used to prohibit line breaks at its position, but this usage was deprecated in Unicode 3.2.[4]