Do your readers a favor: give them an index

Indexing

BLUEPHRASE has indexmark notation which is used to mark passages for inclusion in an index. The notation for this uses special square-bracket doppelmarks that look like this [[ ... ]].

Inside the doppelmarks, there are four types index entries: defining entries, unmarked entries, secondary entries, and cross-reference entries. All four begin with a metatopic, which is an arbitrary name beginning with a dot. In the examples that follow, the metatopic is .bees.

The four types of indexmarks use the following notation:

1. A defining entry consists of a metatopic and the word or phrase that is to be added to the index, delimited with single-quotes, like ' ... '.
2. An unmarked entry consists solely of the metatopic.
3. A secondary entry consists of a metatopic and an alternate word or phrase, which is to be added to the index as a "see also" item, and which is delimited with parentheses, like ( ... ).
4. A cross-reference entry consists of two metatopics.

Here's an example of each type of indexmark:

defining entry [[.bees 'Bees']]
unmarked entry [[.bees]]
secondary entry [[.bees (army)]]
cross-reference entry [[.bees .honey]]

Honey [[.honey 'Honey']]
					

Building the index

The indexmark entries are coalesced into an index where a build pragma occurs. Here's what it might look like:

div {
    h1 Index
    !build-index
}
					

Then, the relevant portion of the emitted output (ignoring all other indexmarks, for brevity) would look like this:

<div>
   <h1>Index</h1>
   ...
   <div class='bees'>
      <dfn><a id=ix25 class='defining' href='#ix20'>Bees</a></dfn>
      <ul>
         <li>also <a id=ix26 class='unmarked' href='#ix21'>1</a></li>
         <li><a id=ix27 class='secondary' href='#ix22'>army</a></li>
         <li><a id=ix28 class='crossref' href='#ix24'>(see also Honey)</a></li>
      </ul>
   </div>
   ...
   <div class='honey'>
      <dfn><a id=ix29 class='defining' href='#ix24'>Honey</a></dfn>
   </div>
   ...
</div>
					

Each entry in the index is hyperlinked back to the original place in the body matter where the indexmark was placed.