To add a new overlay class, all that is required is to write new
“parse” and “suicide” functions, and inform the auto-overlays
package of their existence. A “match” function can also optionally be
defined. It is called whenever a match overlay in the class becomes
matched with the edge of an auto-overlay (see Functions for Modifying Overlays). The parse, suicide and match functions are conventionally
auto-o-match-class, where class is the name of the
class, though the convention is not enforced in any way.
nilif none were created.
o-list = (auto-o-parse-class-match o-match)
Note that the parse function itself is responsible for calling the
auto-o-update-exclusive function if a new exclusive overlay is
created. See Functions for Modifying Overlays.
The text covered by the match overlay should be considered to no longer
match its regexp, although in certain cases matches are ignored for
other reasons and this may not really be the case (for example if a new,
higher-priority, exclusive overlay overlaps the match,
The auto-overlay it is matched with is stored in the match overlay's
To integrate the new class into the auto-overlays package, the parse and suicide functions must be added to the property list of the symbol used to refer to the new class, denoted here by class:
(put 'class 'auto-overlay-parse-function 'auto-o-parse-class-match) (put 'class 'auto-overlay-suicide-function 'auto-o-class-suicide)
If the optional match function is defined, it should similarly be added to the symbol's property list:
(put 'class 'auto-overlay-match-function 'auto-o-match-class)