ଛାଞ୍ଚ:ISO 15924 direction/doc ନିମନ୍ତେ ଆଧାର ଦେଖିବେ

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=== Usage ===
The template returns, for an ISO script code, the direction <code>rtl, ltr, ttb, inh, mixed, or &lt;blank></code>.
* {{tlx|ISO 15924 direction|Hebr}} &rarr; {{ISO 15924 direction|Hebr}} 
* {{tlx|ISO 15924 direction|Latn}} &rarr; {{ISO 15924 direction|Latn}} 

====Options====
The output texts <code>rtl, ltr, ttb, mixed, inh, or &lt;blank></code>:
* {{tlx|ISO 15924 direction|<nowiki>Hebr|ltr=left-to-right|rtl=right-to-left</nowiki>}} &rarr; {{ISO 15924 direction|Hebr|ltr=left-to-right|rtl=right-to-left}}

* {{tlx|ISO 15924 direction|<nowiki>Mong|ttb=top-to-bottom</nowiki>}} &rarr; {{ISO 15924 direction|Mong|ttb=top-to-bottom}}

* {{tlx|ISO 15924 direction|<nowiki>Zyyy|ltr=left-to-right|rtl=right-to-left|mixed=both directions|default=unknown</nowiki>}} &rarr; {{ISO 15924 direction|Zyyy|ltr=left-to-right|rtl=right-to-left|mixed=both directions|default=unknown}}

Output &lt;blank> (meaning: unknown) can be set to show any text:
* {{tlx|ISO 15924 direction|<nowiki>Mang|default=unknown</nowiki>}} &rarr; {{ISO 15924 direction|Mang|default=unknown}}

===How is it determined===
The direction is determined as follows.
* First, if a script is present in [[Unicode]], Unicode Bidi-direction is derived for that Unicode script. 
There are 144 scripts in Unicode (those ISO codes that have an ''alias''). All regular scripts have a single "Strong" in Unicode direction. That is, all characters in a Unicode  script that are "Strong", have the same directionality: either right-to-left (rtl) or left-to-right (ltr). Within a script there are no opposing directions present. There can be characters with "Weak" or "Neutral" direction (i.e., direction through context), but these do not alter other characters diretionality. One exception: script "Zyyy" conatains characters with either direction. Therefor, Zyyy has direction "mixed".

* Second, all other scripts, that are not defined in Unicode, can have their direction set manually in this template.

===How to add a script direction===
The Unicode scripts are current as of version 10.0, and should be complete & correct. That (upper) part of the list should not be changed unless for errors. 
Script directionality can be added:
<pre>
 | <!--
end of Unicode-determined -->
 | Abcd
 | Defg = {{{ltr|ltr}}
 | Pqrs
 | Tuvw = {{{rtl|rtl}}
 | #default={{{default|}}}
</pre>

The parameters as shown keep the output text option available.

===Background===
For scripts in Unicode, the direction is determined as follows. Each character in a script (say Hebr) has a single property [[Character property (Unicode)#bidirectional|bidi-type]]. The value of that bidi-type is [[Template:Bidi Class (Unicode)|from a list]], and its usage is described in the Unicode Bidi Algorithm (UAX#9).

The bidi-type can determine the direction, which can be a Strong, Neutral or Weak one. Strong directions are independent, like for the Latin alphabet A-Z. Neutral and Weak directions are dependent on context (think nearby other characters), and are used e.g. with decimals, diacritics and punctuation marks.

Within the character set of a script (e.g. Hebr=Hebrew script has 133 characters in Unicode), there are Strong characters, ''all are right-to-left''. Other characters are Neutral, and so have not direction by their own. This is true for all (but one) scripts in Unicode: ''within a script, all Strong directions are the same''.

From there this templates is built: All scripts in Unicode (but one exception, see below) have a ''single'' Strong direction. That direction is used here in this template. The exception is: Zyyy, Common, which is a collection of various characters that can be of either direction.

=== See also ===
{{ISO 15924 templates/doc}}
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[[Category:ISO 15924 templates|direction]]

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