Sectionize

This plugin is developed at
Shepherd Interactive
for the benefit of the community. No support is available. Please post any questions to the support forum.

Takes HTML content which contains flat heading elements inline with paragraphs
and automatically nests them withing HTML5

These global WordPress options may be overridden by individual posts/pages by
creating custom fields (postmeta) with the same names.

These options are retreived if their corresponding arguments are not supplied
to the sectionize() function (that is, if they are null):

function sectionize($original_content,
                    $id_prefix = null,
                    $start_section = null,
                    $end_section = null,
                    $include_toc_threshold = null,
                    $before_toc = null,
                    $after_toc = null)

This sectionize() function is added as a filter for the_content (this is
disabled if the option or postmeta sectionize_disabled evaluates to true):

add_filter('the_content', 'sectionize');

Noted above, the TOC is conditionally included. It is not included if:

1. there are no headings in the content (thus there is nothing to sectionize),
2. the headings are not nested properly (see below), or
3. the heading count does not meet the threshold (or the threshold is -1)

If the number of headings in the content is less than the
include_toc_threshold option/argument then the TOC is not displayed;
likewise, if include_toc_threshold is -1 then the TOC is not displayed.

Important! Regarding headings being “nested properly”, you must ensure that
you properly arrange your headings in a hierarchical manner in which no heading
is immediately preceeded by another heading that is more than one level greater
(e.g. an h3 must be preceeded by an h2 or another h3). For example, this
works:

h2
    h3
    h3
        h4
    h3
h2

But this does not:

h2
    h4 -- fail
        h6 -- fail
h2

If you make such a mistake, this plugin will abort and have no effect. An error
notice will be included in the HTML output in the form of an HTML comment.

Please see source code for additional documentation: numerous filters are provided
to further customize the behavior. Be one with the code!
To help serve HTML5 content, see the XHTML5 Support plugin.

2009-11-03: 1.0

• Initial release

2009-12-17: 1.1

• Moved add_option('sectionize_...) calls to activation hook.
• Adding sectionize_toc_text filter so that the link text in the TOC can be customized,
  along with a default filter which strips off tags and a trailing ‘:’