<foreign>
The <foreign> element allows the introduction of non-DITA content,
for example, MathML, SVG, or Rich Text Format (RTF). The <foreign>
element or a specialization can contain more than one type of
non-DITA content or a mix of DITA and non-DITA content. Specialization of the
<foreign> element generally is implemented as a domain, but architects
looking for more control over the content can implement foreign
vocabularies as structural specializations.
Processors should attempt to display <foreign> content unless otherwise instructed. If the processor cannot render the content, it MAY issue a warning.
The enabler of the foreign vocabulary must provide the processing and override the base processing for <foreign>.
- If <foreign> contains more than one alternative content element, they should all be processed. In the case of <desc> they should be concatenated in a similar way to <section>, but with no title (analogous to <div> in HTML).
- If alternate content is desired, specialize the <desc> element to contain it. This specialization of <desc> should be used within the element specialized from <foreign>. Such alternate content must of course be valid wherever the <foreign> specialization is valid.
- If no <desc>, <object>, or <image> element is found within an instance of the <foreign> element, the base processing can emit a warning about the absence of processable content.
- The base processing for <object> might emit the content of <foreign> as a file at the location specified by the @data attribute of the <object> element. The <object> element should have a data attribute or a <foreign> sub-element but not both. In the event that an <object> element contains both a data attribute and an <foreign> sub-element the processing system should ignore one of them.
Content models
See appendix for information about this element in OASIS document type shells.
Inheritance
- topic/foreign
SVG Example within a <p> element
<p>... as in the formula
<svg>
<svg:svg width="100%" height="100%" version="1.1"
xmlns="http://www.w3.org/2000/svg">
<ellipse cx="300" cy="150" rx="200" ry="80"
style="fill:rgb(200,100,50);
stroke:rgb(0,0,100);stroke-width:2"/>
</svg:svg>
</svg>.
</p> MathML Example within an <object> element
<p>... as in the formula
<object>
<desc>4 + x</desc>
<mathml>
<m:math display="block">
<m:mrow>
<m:mo>sum</m:mo>
<m:mn>4</m:mn>
<m:mo>+</m:mo>
<m:mi>x</m:mi>
</m:mrow>
</m:math>
</mathml>
</object>.
</p>
Attributes
The following attributes are available on this element: Universal attribute group and @outputclass.