Getting HelpYou can get help on Epsilon by typing F1, the help key. The help key will provide help at any time. If you type it during another command, help simply pops up a description of that command. Otherwise, the help command asks you to type an additional key to indicate what sort of help you want. Many of these options are also available directly from Epsilon's Help menu item, in versions with a menu bar.
The help command actually uses various commands which you can invoke individually. Here are the keys you can use at the help prompt.
Pressing A invokes the apropos command, which asks for a string, looks through the one-line descriptions of all the commands and variables, then pops up a list of commands or variables (and their descriptions) that contain the string, along with their key bindings. Highlighted words are links to the full documentation.
(The Info, HTML-based, and WinHelp formats of Epsilon's full manual each include their own search function. These will perform full-text searches throughout Epsilon's manual, often finding many more matches than apropos finds by searching one-line descriptions.)
Help's K option invokes the describe-key command. It prompts for a key and provides full documentation on what that key does.
The C option invokes the command describe-command, which provides full documentation on the command whose name you specify, and also tells which keys invoke that command.
The B option invokes the command show-bindings, which asks for a command name and gives you the keys that run that command.
The F option is a shortcut into Epsilon's manual in Info mode. It prompts for some text, then looks up that text in the index of Epsilon's online manual. Just press <Enter> to go to the top of the manual. This option invokes the command epsilon-info-look-up; the command epsilon-manual-info goes to the top of Epsilon's documentation without prompting.
The Ctrl-C option prompts for the name of an Epsilon command, then displays an Info page from Epsilon's online manual that describes the command.
The Ctrl-K option prompts for a key, then displays an Info page from Epsilon's online manual that describes the command it runs.
The Ctrl-V option prompts for an Epsilon variable's name, then displays an Info page from Epsilon's online manual that describes that variable.
The H option displays Epsilon's manual in HTML format, by running a web browser. It prompts for a topic, which can be a command or variable name, or any other text. (The browser will try to find an exact match for what you type; if not, it will search for web pages containing that word.) When you're looking at Epsilon's manual in Info mode, using one of the previous commands, this command will default to showing the same topic in a browser.
The W option, in Epsilon for Windows versions prior to Vista, displays Epsilon's WinHelp help file. Like the Info-format manual, it contains the complete text of the Epsilon manual. (Windows Vista and later no longer support WinHelp natively, so such users should select HTML or Info help formats instead. It's possible to install WinHelp onto later Windows systems, then enable its macros with a registry entry, if you prefer this style of help. See Microsoft's web site.)
The Q option invokes the command what-is, which asks for a key and tells you what command would run if you typed that key.
The R option invokes the describe-variable command, which asks for a variable name and displays the help on that variable.
The L option invokes the show-last-keys command, which pops up a window that displays the last 60 keystrokes you typed.
The M option displays help on the major mode of the current buffer. For example, when you're editing a C file, this command displays help on C mode.
The T option shows context-sensitive help on the word at point. The help source varies based on the buffer's mode. See Context-Sensitive Help.
The V command displays Epsilon's version number and similar information.
The ? option displays information on the help command itself, including its options, just as typing the help key again would.
The B and Q options tell you about bindings without showing you the associated documentation on the command. In contrast to the first three options, these two display their information in the echo area, instead of popping up a window.
The wall-chart command creates a table showing the commands invoked by all the keys. It builds a chart in a buffer named "wall". The wall chart includes any changes you may have made to the normal key bindings. You can print it and attach it to any convenient wall using the print-buffer command.
Epsilon's help system keeps track of any changes that you make to Epsilon. For example, if you completely remap the keyboard, Epsilon's help system will know about it and still give you correct key binding information. And Epsilon's help system will also keep track of any commands or keyboard macros that you write and add to Epsilon.
The release-notes command reads and displays the release notes for this version of Epsilon.
Some of Epsilon's help commands use the on-line documentation file, edoc. This file contains descriptions for each of Epsilon's commands and variables. See the description of the -fd flag in Epsilon Command Line Flags.
While some help commands provide help using a specific format like WinHelp or HTML help, others change their format based on the current platform. For instance, pressing the help key at a prompt shows help using WinHelp on earlier Windows systems, using HTML help on Vista and later Windows version (which don't include WinHelp) and on Unix under X11, and using popup help windows on Unix systems in console mode. You can select a different preferred help format by setting the variables epsilon-help-format-win-gui, epsilon-help-format-win-console, and epsilon-help-format-unix-gui.