Separation of Concerns for Indexing

Separation of concerns is a fundamental principle for managing conplex tasks. Previous tools for assisting in generating back-of-the-book indexes do not apply this principle as thoroughly as they might; in particular, most confuse two issues: recording where references occur in the main text, and deciding what terms should appear in the index. This paper describes a general facility for multi-level indexes that embodies this principle, usable in any document formatter that can produce a secondary output file recording page numbers where references occur. LATEX, Scribe, and nroff/troff fall in this category.