Separation of concerns for indexing

Abstract

Separation of concerns is a fundamental principlefor managing conplex tasks. Previous tools forassisting in generating back-of-the-book indexes donot apply this principle as thoroughly as theymight; 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 formulti-level indexes that embodies this principle,usable in any document formatter that can produce asecondary output file recording page numbers wherereferences occur. {\LaTeX}, {\bf Scribe}, and {\bfnroff}/{\bf troff} fall in this category.