5.2 Directions

A variety of data items, called element directions, are associated with element units. They may be used in the formatting functions, and/or associated with a button (see Simple Navigation Panel Customization).

Each element direction has a name and a reference to the element unit they point to, when such an element exists. The element is either a global element unit (for example, the Top element) or relative to the current element unit (for example, the next element unit). Such relative elements are determined with respect to the document structure defined by the section structuring commands (@chapter, @unnumbered…) or by the nodes if the node pointers are specified on @node lines or in menus (see Two Paths in Texinfo).

Here is the list of global element units directions:

 

An empty button.

Top

Top element.

About

About (help) page.

Contents

Table of contents.

Overview

Overview: short table of contents.

Footnotes

Corresponds to the Footnotes element (see Output Element Units).

Index

The first element unit with @printindex.

Here is the list of relative element units directions:

This

The current element unit.

Forward

Next element unit in reading order.

First

First element unit in reading order.

Last

Last element unit in reading order.

Back

Previous element unit in reading order.

FastForward

Next chapter element unit.

FastBack

Beginning of this chapter, or previous chapter if the element is a chapter.

Next

Next section element unit at the same level.

Prev

Previous section element unit at the same level.

Up

Up section.

SectionNext

Next element unit in section reading order.

SectionPrev

Previous element unit in section reading order.

SectionUp

Up in section reading order.

NodeNext

Next node element unit.

NodeForward

Next node element unit in node reading order.

NodeBack

Previous node element unit in node reading order.

NodePrev

Previous node element unit.

NodeUp

Up node element unit.

Relative direction elements are each associated to a variant, with ‘FirstInFile’ prepended, which points to the direction relative to the first element in file. For example, FirstInFileNodeNext is the next node element relative to the first element in file. The ‘FirstInFile’ directions are usually used in footers.