programlistingco — A program listing with associated areas used in callouts
Callouts, such as numbered bullets, are an annotation mechanism. In an online system, these bullets are frequently “hot,” and clicking on them sends you to the corresponding annotation.
programlistingco is a wrapper around an
areaspec and a
areaspec identifies the locations (coordinates) in
programlisting where the callouts occur. The
programlistingco may also contain the list of
annotations in a
calloutlist, although the
calloutlist may also occur outside the wrapper,
elsewhere in the document.
It is also possible to embed
directly in the verbatim text, in order to avoid having to calculate the
correct coordinates. If you decided to go this route, use a
programlisting and a
calloutlist without the
programlistingco wrapper. A
programlistingco must specify at least
For a complete description of callouts, see
Formatted as a displayed block. This element is displayed “verbatim”; whitespace and line breaks within this element are significant.
The mandatory processing expectations of a
programlistingco are minimal: a system is expected
to render the program listing and the callout list, if present.
co elements are embedded in a