What are the various indexing packages and what are their pros and cons? When should one choose one over the other?
There is some discussion of this in What are the latest/best practices for index generation?, but I would prefer to have more details about each package.
Best Answer
The features provided by the various indexing packages may be divided into three categories:
Supporting multiple indexes;
Providing macros that simplify index generation;
Allowing for customization of the index layout.
The
Topic Index
of the TeX Catalogue lists about a dozen index-related packages; this overview is about the packages I've used (or at least read the manual).makeidx
, a "[s]tandard package for creating indexes", provides some index-related macros like\printindex
which (for whatever reason) are not part of the LaTeX2e kernel (like\makeindex
and\index
) or the standard document classes (like thetheindex
environment).multind
"redefines [the]\makeindex
,\index
and\printindex
commands to deal with multiple indexes". The package predates LaTeX2e; it doesn't work with the AMS classes, and index headings won't be formatted corresponding to other chapter/section headings.index
"supports multiple indexes in a single document and provides a more robust\index
command". The package also offers\index*
which typesets a word and creates an index entry for it as well.index
is likely to produce incorrectly formatted index headings for non-standard classes.splitidx
/splitindex allow "more than 16 indexes:splitidx
outputs only a single file\jobname.idx
and the program [splitindex] splits that file into several raw index files and calls your favorite index processor for each of the files". Thesplitidx
package offers the\extendtheindex
macro that adds various hooks to thetheindex
environment; the actual customization of the latter is left to the user.imakeidx
"enables the user to produce and typeset one or more indexes simultaneously with a document" by using the shell-escape feature of modern TeX distributions.imakeidx
is able to call the splitindex program (see above), and it features a key--value interface to customize various aspects of the index layout (including the possibility to call the MakeIndex program with a certain.ist
style file). Originally,imakeidx
was not compatible with thememoir
class (which uses an idiosyncratic method to generate indexes), but v1.1 of the package does away with that restriction.hvindex
"simplifies the indexing of words [...] [T]o index a word in a text, you only have to type it once; the package makes sure it is both typeset and indexed". The package offers a bunch of macros that control the formatting of index entries; the package manual is silent about whether those macros may be used for the creation of multiple indexes.idxlayout
"offers a key--value interface to configure index layout parameters [and] is responsive to the index-related options and commands of theKOMA-Script
andmemoir
classes".idxlayout
does only deal with thetheindex
environment, not with.ist
style files; it may be used on top ofindex
,splitidx
, andimakeidx
. (Disclosure: I'm the package author.)repeatindex
"repeats [the] item of an index if a page or column break occurs within a list of subitems". The package README (from 2001) states thatrepeatindex
"has not been tested much, yet" and lists some known problems.indextools
is a modern fork by Maïeul Rouquette ofimakeidx
that introduces compatibility withbidi
for bi-directonal language typesetting.