-\1f
-File: xemacs.info, Node: Changing an Option, Next: Face Customization, Prev: Customization Groups, Up: Easy Customization
-
-Changing an Option
-..................
-
- Here is an example of what a user option looks like in the
-customization buffer:
-
- Kill Ring Max: [Hide] 30
- [State]: this option is unchanged from its standard setting.
- Maximum length of kill ring before oldest elements are thrown away.
-
- The text following `[Hide]', `30' in this case, indicates the
-current value of the option. If you see `[Show]' instead of `[Hide]',
-it means that the value is hidden; the customization buffer initially
-hides values that take up several lines. Invoke `[Show]' to show the
-value.
-
- The line after the option name indicates the "customization state"
-of the option: in the example above, it says you have not changed the
-option yet. The word `[State]' at the beginning of this line is
-active; you can get a menu of various operations by invoking it with
-`Mouse-1' or <RET>. These operations are essential for customizing the
-variable.
-
- The line after the `[State]' line displays the beginning of the
-option's documentation string. If there are more lines of
-documentation, this line ends with `[More]'; invoke this to show the
-full documentation string.
-
- To enter a new value for `Kill Ring Max', move point to the value
-and edit it textually. For example, you can type `M-d', then insert
-another number.
-
- When you begin to alter the text, you will see the `[State]' line
-change to say that you have edited the value:
-
- [State]: you have edited the value as text, but not set the option.
-
- Editing the value does not actually set the option variable. To do
-that, you must "set" the option. To do this, invoke the word `[State]'
-and choose `Set for Current Session'.
-
- The state of the option changes visibly when you set it:
-
- [State]: you have set this option, but not saved it for future sessions.
-
- You don't have to worry about specifying a value that is not valid;
-setting the option checks for validity and will not really install an
-unacceptable value.
-
- While editing a value or field that is a file name, directory name,
-command name, or anything else for which completion is defined, you can
-type `M-<TAB>' (`widget-complete') to do completion.
-
- Some options have a small fixed set of possible legitimate values.
-These options don't let you edit the value textually. Instead, an
-active field `[Value Menu]' appears before the value; invoke this field
-to edit the value. For a boolean "on or off" value, the active field
-says `[Toggle]', and it changes to the other value. `[Value Menu]' and
-`[Toggle]' edit the buffer; the changes take effect when you use the
-`Set for Current Session' operation.
-
- Some options have values with complex structure. For example, the
-value of `load-path' is a list of directories. Here is how it appears
-in the customization buffer:
-
- Load Path:
- [INS] [DEL] [Current dir?]: /usr/local/share/emacs/19.34.94/site-lisp
- [INS] [DEL] [Current dir?]: /usr/local/share/emacs/site-lisp
- [INS] [DEL] [Current dir?]: /usr/local/share/emacs/19.34.94/leim
- [INS] [DEL] [Current dir?]: /usr/local/share/emacs/19.34.94/lisp
- [INS] [DEL] [Current dir?]: /build/emacs/e19/lisp
- [INS] [DEL] [Current dir?]: /build/emacs/e19/lisp/gnus
- [INS]
- [State]: this item has been changed outside the customization buffer.
- List of directories to search for files to load....
-
-Each directory in the list appears on a separate line, and each line has
-several editable or active fields.
-
- You can edit any of the directory names. To delete a directory from
-the list, invoke `[DEL]' on that line. To insert a new directory in
-the list, invoke `[INS]' at the point where you want to insert it.
-
- You can also invoke `[Current dir?]' to switch between including a
-specific named directory in the path, and including `nil' in the path.
-(`nil' in a search path means "try the current directory.")
-
- Two special commands, <TAB> and `S-<TAB>', are useful for moving
-through the customization buffer. <TAB> (`widget-forward') moves
-forward to the next active or editable field; `S-<TAB>'
-(`widget-backward') moves backward to the previous active or editable
-field.
-
- Typing <RET> on an editable field also moves forward, just like
-<TAB>. The reason for this is that people have a tendency to type
-<RET> when they are finished editing a field. If you have occasion to
-insert a newline in an editable field, use `C-o' or `C-q C-j',
-
- Setting the option changes its value in the current Emacs session;
-"saving" the value changes it for future sessions as well. This works
-by writing code into your `~/.emacs' file so as to set the option
-variable again each time you start Emacs. To save the option, invoke
-`[State]' and select the `Save for Future Sessions' operation.
-
- You can also restore the option to its standard value by invoking
-`[State]' and selecting the `Reset' operation. There are actually
-three reset operations:
-
-`Reset to Current'
- If you have made some modifications and not yet set the option,
- this restores the text in the customization buffer to match the
- actual value.
-
-`Reset to Saved'
- This restores the value of the option to the last saved value, and
- updates the text accordingly.
-
-`Reset to Standard Settings'
- This sets the option to its standard value, and updates the text
- accordingly. This also eliminates any saved value for the option,
- so that you will get the standard value in future Emacs sessions.
-
- The state of a group indicates whether anything in that group has
-been edited, set or saved. You can select `Set for Current Session',
-`Save for Future Sessions' and the various kinds of `Reset' operation
-for the group; these operations on the group apply to all options in
-the group and its subgroups.
-
- Near the top of the customization buffer there are two lines
-containing several active fields:
-
- [Set] [Save] [Reset] [Done]
-
-Invoking `[Done]' buries this customization buffer. Each of the other
-fields performs an operation--set, save or reset--on each of the items
-in the buffer that could meaningfully be set, saved or reset.