Template:Unichar/doc

This template produces a formatted description of a Unicode character, to be used inline with regular text.
 * The character is about intellectual property.
 * The character is about intellectual property.

Usage
This template produces a formatted description of a Unicode character, to be used in-line with regular text. It needs Unicode hexadecimal value (mandatory) and all-caps name (usually) as input, like  →.

It follows the standard Unicode presentation of a character such as using the pattern "U+00A9", and reformatting Unicode's all-caps naming convention (which is undesired in Wikipedia text, looking like BLOG-STYLE SCREAMING EMPHASIS) by using the less visually interruptive. The hexadecimal value is required (e.g. A9), other input is optional. The actual glyph is rendered using a font that contains the character. This can be set to something more specific, e.g. to language- or IPA-specific fonts. To show the glyph, the font character can be overridden with an image. A wikilink to an article on the character or set of characters, and another to the article Unicode can be created. It is also possible to add (bracketed like this), the calculated decimal value, HTML character codes, and a custom note.

Some special code points are given extra care, like control and space characters. These are automatically detected by the  sub-template.

Bad examples

 * → – broken because there's no name to link
 * → – broken because COPYRIGHT SIGN doesn't redirect to our actual article, Copyright symbol

Parameters
The blank template, with all parameters, is as follows:

Inline version:


 * First unnamed parameter or 1= Required. The hexadecimal value of the code point, e.g. 00A9.
 * Notes: The parameter accepts input like A9, a9 and 00A9 as hexadecimal value. Decimal values are not detected being decimal, and will give unexpected results.
 * Second unnamed parameter or 2= Optional. The Unicode name of the character. This is given in ALL-CAPS, and the template will re-render it in . This name may differ from the title of the corresponding Wikipedia article (see below: nlink=).
 * nlink= Optional wikilink. Name of the Wikipedia page that will be linked to. If used, the Unicode name (second parameter) has a wikilink to the article.
 * Warning: This parameter must have valid value if it is present; if present and empty, a red-link error will appear unless a redirect from the formal Unicode symbol name like COPYRIGHT SIGN exists and goes to the correct article here (in this case Copyright symbol. Eventually all of these redirects should exist, but few do
 * Note: The name of the page is case-sensitive as with all Wikipedia pages.
 * &rarr;
 * ulink Optional. Creates a wikilink from the U+ prefix. When used without a name (i.e., undefined, blank with no value), the article Unicode is used as the default value in the output: U+ producing U+. This only needs to change if you have a reason to link elsewhere than Unicode, e.g. to an article on a subset of Unicode characters.
 * dec= Optional. Adds the decimal value to the text, in the bracketed note. You do not need to add the value manually; just add dec, blank.
 * html= Optional. Adds the HTML character reference to the text, like &amp;#160; in the bracketed note. If a named character reference exists, like "&amp;nbsp;", that is added too. You do not need to add the values manually, just add html, blank.
 * use= Optional. Sets the font-hinting template to get the glyph, since the character may not be present in a regular browser font. Default is, other options are , and.
 * use2= Optional. When setting lang or script, use2 should be used to set the language (e.g. fr) or the script (e.g. Cyrs). A glyph may still not show as expected due to browser effects. For a detailed description, see each template's documentation.
 * &rarr;
 * image= Optional. Allows for a graphic image file to represent the glyph; overrides the font completely. The filename should include the extension (like .svg or .png ), but the prefix File:.
 * cwith= Optional. Useful when the Unicode character is . Using cwith adds a space before the character, allowing the combining effect. So when used with a character like a, the character will be combined with the letter "a". In Unicode, a general glyph used to place a combined character is.
 * without cwith:
 * &rarr;
 * cwith without parameter:
 * &rarr;
 * cwith with dotted circle:
 * &rarr;
 * size= Optional. Can be used to set the size of the glyph. The default value is 125% . For the font, all CSS font-size style inputs are accepted: 7px, 150% , 2em , larger.
 * &rarr;
 * When using an image (file) instead of a font, this size can only accept sizes in px like 12px . Default for images is 10px.

Produces:

Presentation effects
Since this template is aimed at presenting a formatted, inline description, some effects are introduced to sustain this target.
 * Showing space characters: All space characters (those with General Category: Zs) are presented with a light-blue background, to show their actual presence and width:.
 * Incidentally, the regular space is replaced with   (NBSP) to prevent wiki-markup deleting it as repeated spaces.
 * Removing formatting characters: Formatting characters (those with General Category: Cf, Zl and Zp) are removed from the output. By definition, formatting characters have no glyph. By removing them they cannot have a formatting effect.
 * Exception: five Arabic Cf/formatting number markings U+0600..U+0603 and U+60DD, are shown. While Cf formatting characters usually have no glyph, these five have. By internally adding "(visible)" to the category, these characters are shown.
 * Removing whitespace: The template removes formatting code and surrounding whitespace from the input. A  in the Name-input (possibly unintended) would frustrate the in-line behaviour expectation.
 * Showing a label like : Unicode states that a code point has no name when it is one of these: a control character, a private use character, a surrogate, a not assigned code point (reserved), or a non-character. These code points instead should be referred to by using a "Code Point Label", such as  or . In this situation, this template replaces the glyph with that label. This way, the correct presentation wins it over Unicode-usage to the letter of the law.
 * "Control" general category=Cc:  or
 * "Surrogate" general category=Cs:  or
 * "Private Use": general category=Co:  or
 * "Not a character" (minus the reserved code points, see below): general category=Cn:,   or

The second parameter (Unicode name) is not presented, since it cannot exist. It is possible to create a link to an article.
 * Note: A (unassigned) code point cannot be detected yet, and so is not presented with this label. These code points too are given Cn category.
 * (Background on <>-labels: A Name can never have <>-brackets at all. These rules prevent mixing up a name with an actual control-character. So it will not happen that a bell rings when a page is opened that contains a Name of U+0007).

Possible errors

 * The template produces an when 1 (or first unnamed parameter), the hex value, is missing, empty, or invalid.
 * A non-hexadecimal input like 00G9 produces an error (because G or g is not hexadecimal).
 * Do not add the U+ prefix, as in U+00A9. It will not be recognised.
 * If the template shows the code point number, like 2038, you're probably using the wrong template, , instead of.
 * The glyph may be overruled and changed into a like &lt;control-0007&gt; . These characters have no Unicode name. An nlink will be directly to the article (entered in a form like Bell signal). A blank value of just undefined cannot work for &lt;label-hhhh&gt; characters (there is no character name at all to make into a link). This produces an error.
 * A decimal-value input like 98 will be read as being hexadecimal value 0098 . There is that the template can detect you intended to enter 9810=6216 . No warning is issued, and the wrong character, U+009816, will be shown ( U+0062 ).
 * As noted above, misuse of the nlink parameter may result in red links to articles that don't exist.

Technical notes
The string "unichar" is used only in English Wikipedia, as a name for this template. It has no meaning outside this context.

The template uses these subtemplates:
 * unichar/main Accepts all the input from . Calls several subtemplates to produce the textstrings, and then strings them together. Also checks for the error non-hex input.
 * unichar/ulink Creates a piped link for the U+ prefix.
 * unichar/gc Determines the Unicode general category, when this category is special (like, for control characters).
 * unichar/glyph For rendering the glyph by font. Accepts image, which overrides the font. Also processes use, use2, size, cwith.
 * unichar/na Produces the formatted name of the character in . Accepts the nlink to create a piped wikilink to an article. When the general category (gc) is special, the name will change into a &lt;label-hhhh&gt;.
 * unichar/notes Produces the three optional notes in parentheses (round brackets): decimal (from dec); HTML (from html – both decimal like &amp;#160; and named like &amp;nbsp; if that exists, using ); and the free-text note. Also does the parentheses themselves.
 * Using the main template as an easy-input feature, there are few calculations done (actually only two hex2dec), and allows for adding default values not too deep in the templates.
 * The value  is used internally to pass through a non-defined input parameter. This value is correct when about the Unicode name, because it cannot have the characters <##>, and so salted is the right word (meaning uninhibitable). For ease of code maintenance, it is used in various places in the code.

Issues

 * Unassigned code points, to be labelled, cannot be detected.
 * When using use-script, then use2 needs lowercase (e.g. 0485, Cyrs or cyrs)
 * When using for one of the RTL formatting marks, its effect may break out of the template (text following the template goes RTL, too). As it is now, this requires extra code.

TemplateData
{	"params": { "1": {},		"2": {},		"ulink": {}, "image": {}, "cwith": {}, "size": {}, "use": {}, "use2": {}, "nlink": {}, "dec": {}, "html": {}, "HTML": {}, "note": {} },	"description": "Formats a Unicode character description. INline." }

See also, external links
Useful links for researching Unicode characters:
 * Unicode.org charts in PDF format, showing the U+ hex values.
 * Fileformat.com search, to search by name (whole or partial), by U+ hex value or decimal value, or by the font symbol (copy-paste it). Extra information provided per character. One character only.
 * branah.com's a multi-character Unicode converter.