Learning GNU Emacs, Second Edition

Using Outline Mode

When you’re writing something, whether it’s a book, a long memo, or a technical specification, getting a sense of organization as you go along is frequently difficult. Therefore, it is often difficult to expand an outline smoothly into a much longer paper or to reorganize a paper as you go along. The words get in the way of your headings, making it hard to see the forest for the trees.

Outline mode provides a built-in solution to this problem. This mode gives you the ability to hide or display text selectively, based on its relationship to the structure of your document. For example, you can hide all of your document’s text except for its headings; thereby giving you a feel for the document’s shape. When you’re looking at the headings, you can focus on structure without being concerned about the individual words; then, when you’ve solved your structural problems, you can make the words reappear.

Outline mode is more useful for documents with several levels of headings (or for long programs) than for plain outlines containing very little text. The longer a document is, the harder it is to get a quick feel for the overall structure; it is in such a situation that outline mode’s ability to hide and show portions of the text comes in handy.

For all of outline mode’s advantages, a word of caution is in order. There are a number of ways to mangle a document using outline mode if you are inexperienced. You may wish to format a copy of your document in outline mode (easy ...