View source for Template:Var serif/doc

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==Usage==
This template is to help facilitate the displaying of variable names (in mathematics, computer source code, etc.) with the semantically correct <code><nowiki><var>...</var></nowiki></code>, which also renders the variable in italics, as is customary, ''and'' to do so in a serif font. This is ''specifically'' for the use of the characters "I" (upper-case i) and "l" (lower-case L), which in many sans-serif fonts can be difficult to distinguish. The template also very slightly adjusts the font size of the enclosed variable, to account for typical difference in [[x-height]] between non-fancy serif (e.g., Times and Times New Roman) and sans-serif (e.g. Arial and Helvetica) typefaces.  The template should not be used generally, but only for "I" and "l", and perhaps other cases where a known visual ambiguity can be shown to exist in common sans-serif fonts for readers without acute vision.  It is recommended to use {{tlx|var|1}} rather than {{tlx|var serif|1}} for "1" (numeral one), as it is usually more clearly distinguishable from "I" and "l" in sans-serif than serif fonts.

{{tlx|Var serif}} need not be used for variables that simply ''contain'' "I" or "l", only for cases in which readers are likely to be unable to distinguish them visually.

The {{tlx|var serif}} method is preferred to simply italicizing and using inline style to specify the font, for [[WP:Accessibility|accessibility]], [[Separation of presentation and content|content/presentation separation]], [[semantic Web]], and [[WP:METADATA|metadata]] reasons; XHTML's <code><nowiki><var></nowiki></code> element has semantic meaning, while simple font changes like italicizing does not.

Because the font styling in the template is done entirely with [[Cascading Style Sheets|CSS]], it has no effect at all upon content semantics, nor does it change the output for users of [[screen reader]] software.

Example: 
: <code><nowiki>{{var serif|I}}</nowiki></code>
outputs:
: <code><nowiki><var style="font-size:118%;font-family:serif;">I</var></nowiki></code>
which renders as:
: {{var serif|I}}

;Comparisons:
: <code><nowiki>{{var|I}}</nowiki></code> = {{var|I}}
: <code><nowiki>{{var|l}}</nowiki></code> = {{var|l}}
: <code><nowiki>{{var|1}}</nowiki></code> = {{var|1}}
: <code><nowiki>{{var serif|I}}</nowiki></code> = {{var serif|I}}
: <code><nowiki>{{var serif|l}}</nowiki></code> = {{var serif|l}}
: <code><nowiki>{{var serif|1}}</nowiki></code> = {{var serif|1}}

Please note that {{tnull|var serif}} is not a panacea; its treatment of the numeral "1" is easily mistaken for the letter "l" (lower-case "L") in many serif fonts.

; Recommended usage:
: <code><nowiki>{{var serif|I}}</nowiki></code> = {{var serif|I}}
: <code><nowiki>{{var serif|l}}</nowiki></code> = {{var serif|l}}
: <code><nowiki>{{var|1}}</nowiki></code> = {{var|1}}
: <code><nowiki>{{var|</nowiki>{{var|variable}}<nowiki>}}</nowiki></code> for any other variable

==TemplateData==
{{TemplateDataHeader}}
<templatedata>
{
	"params": {
		"1": {},
		"class": {},
		"id": {},
		"style": {},
		"lang": {},
		"title": {}
	}
}
</templatedata>

{{Semantic markup templates|show}}

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