Indexing commands

Here are the commands.

• \sidx{term}[subterm] makes an index entry for term, optionally with subterm subterm. \idx{term} also produces term as output. Example:

  \sidx{truth}[beauty of]
  The beauty of truth is \idx{death}.
  

• \sidxname{First M.}{von Last}[subterm] makes an index entry for `von Last, First M.'. You can change the `, ' by redefining \idxnameseparator. \idxname{First M.}{von Last} also produces First M. von Last as output. (These commands are useful special cases of \idx and \sidx.) Example:

  \sidxname{Richard}{Stark}
  \idxname{Donald}{Westlake} has written many kinds of novels, under
  almost as many names.
  

• \sidxmarked\cs{term}[subterm] makes an index entry for term[subterm], but term will be put in the index as \cs{term}, but still sorted as just term. \idxmarked\cs{term} also typesets \cs{term}. This provides for the usual ways of changing the typesetting of index entries. Example:

  \def\article#1{"#1"}
  \sidxmarked\article{Miss Elsa and Aunt Sophie}
  Peter Drucker's \idxmarked\article{The Polanyis} is a remarkable essay
  about a remarkable family.
  

• \sidxsubmarked{term}\cs{subterm} makes an index entry for term, subterm as usual, but also puts subterm in the index as \cs{term}. \idxsubmarked{term}\cs{subterm} also typesets term \cs{subterm}, in the unlikely event that your syntax is convoluted enough to make this useful. Example:

  \def\title#1{{\sl #1}}
  \sidxsubmarked{Anderson, Laurie}\title{Strange Angels}
  The \idxsubmarked{Anderson}\title{Carmen} is a strange twist.
  

The commands above rely on MakeIndex's feature for separating sorting of an index entry's from its typesetting. You can use this directly by specifying an index entry as sort@typeset. For example:

\sidx{Ap-weight@$A_\pi$-weight}

will sort as Ap-weight, but print with the proper math. The @ here is MakeIndex's default character for this purpose. See section `Style File-MakeIndex' in MakeIndex. To make an index entry with an @ in it, you have to escape it with a backslash; Eplain provides no macros for doing this.

After any index command, Eplain runs \hookaction{afterindexterm}. Because the index commands always add a whatsit item to the current list, you may wish to preserve a penalty or space past the new item. For example, given a conditional \if@aftersctnhead set true when you're at a section heading, you could do:

\hookaction{afterindexterm}{\if@aftersctnhead \nobreak \fi}