@end example
At the appropriate time, Emacs uses the @code{run-hooks} function to
-run particular hooks. This function calls the hook functions that have
-been added with @code{add-hook}.
+run particular hooks.
@defun run-hooks &rest hookvars
This function takes one or more normal hook variable names as
@item
If you want to make the new mode the default for files with certain
recognizable names, add an element to @code{auto-mode-alist} to select
-the mode for those file names. If you define the mode command to
-autoload, you should add this element in the same file that calls
-@code{autoload}. If you use an autoload cookie for the mode command,
-you can also use an autoload cookie for the form that adds the element
-(@pxref{autoload cookie}). If you do not autoload the mode command,
-it is sufficient to add the element in the file that contains the mode
-definition. @xref{Auto Major Mode}.
+the mode for those file names (@pxref{Auto Major Mode}). If you
+define the mode command to autoload, you should add this element in
+the same file that calls @code{autoload}. If you use an autoload
+cookie for the mode command, you can also use an autoload cookie for
+the form that adds the element (@pxref{autoload cookie}). If you do
+not autoload the mode command, it is sufficient to add the element in
+the file that contains the mode definition.
@item
In the comments that document the file, you should provide a sample
@code{:syntax-table} keyword (see below). @code{define-derived-mode}
makes the parent mode's syntax-table the parent of
@code{@var{variant}-syntax-table}, unless the latter is already set
-and already has a parent different from @code{standard-syntax-table}.
+and already has a parent different from the standard syntax table.
@item
The new mode has its own abbrev table, kept in the variable
@item
The new mode has its own mode hook, @code{@var{variant}-hook}. It
runs this hook, after running the hooks of its ancestor modes, with
-@code{run-mode-hooks}.
+@code{run-mode-hooks}, as the last thing it does. @xref{Mode Hooks}.
@end itemize
In addition, you can specify how to override other aspects of
@var{parent} with @var{body}. The command @var{variant}
evaluates the forms in @var{body} after setting up all its usual
-overrides, just before running @code{@var{variant}-hook}.
+overrides, just before running the mode hooks.
You can also specify @code{nil} for @var{parent}. This gives the new
mode no parent. Then @code{define-derived-mode} behaves as described
are evaluated. The following keywords are currently supported:
@table @code
-@item :group
-If this is specified, it is the customization group for this mode.
-
@item :syntax-table
You can use this to explicitly specify a syntax table for the new
mode. If you specify a @code{nil} value, the new mode uses the same
-syntax table as @var{parent}, or @code{standard-syntax-table} if
+syntax table as @var{parent}, or the standard syntax table if
@var{parent} is @code{nil}. (Note that this does @emph{not} follow
the convention used for non-keyword arguments that a @code{nil} value
is equivalent with not specifying the argument.)
@item :abbrev-table
You can use this to explicitly specify an abbrev table for the new
mode. If you specify a @code{nil} value, the new mode uses the same
-abbrev-table as @var{parent}, or @code{fundamental-mode-abbrev-table}
-if @var{parent} is @code{nil}. (Again,a @code{nil} value is
+abbrev table as @var{parent}, or @code{fundamental-mode-abbrev-table}
+if @var{parent} is @code{nil}. (Again, a @code{nil} value is
@emph{not} equivalent to not specifying this keyword.)
+
+@item :group
+If this is specified, the value should be the customization group for
+this mode. (Not all major modes have one.) Only the (still
+experimental and unadvertised) command @code{customize-mode} currently
+uses this. @code{define-derived-mode} does @emph{not} automatically
+define the specified customization group.
@end table
Here is a hypothetical example:
@item
Add an element to @code{minor-mode-alist} for each minor mode
-(@pxref{Mode Line Variables}), if you want to indicate the minor mode in
-the mode line. This element should be a list of the following form:
+(@pxref{Definition of minor-mode-alist}), if you want to indicate the
+minor mode in the mode line. This element should be a list of the
+following form:
@smallexample
(@var{mode-variable} @var{string})
invoking the mode command. Note in the variable's documentation string that
setting the variable other than via Custom may not take effect.
- Also mark the definition with an autoload cookie (@pxref{Autoload}),
+ Also mark the definition with an autoload cookie (@pxref{autoload cookie}),
and specify a @code{:require} so that customizing the variable will load
the library that defines the mode. This will copy suitable definitions
into @file{loaddefs.el} so that users can use @code{customize-option} to
Each minor mode can have its own keymap, which is active when the mode
is enabled. To set up a keymap for a minor mode, add an element to the
-alist @code{minor-mode-map-alist}. @xref{Active Keymaps}.
+alist @code{minor-mode-map-alist}. @xref{Definition of minor-mode-map-alist}.
@cindex @code{self-insert-command}, minor modes
One use of minor mode keymaps is to modify the behavior of certain
Any other keyword arguments are passed passed directly to the
@code{defcustom} generated for the variable @var{mode}.
-The command named @var{mode} finishes by executing the @var{body} forms,
-if any, after it has performed the standard actions such as setting
-the variable named @var{mode}.
+The command named @var{mode} first performs the standard actions such
+as setting the variable named @var{mode} and then executes the
+@var{body} forms, if any. It finishes by running the mode hook
+variable @code{@var{mode}-hook}.
@end defmac
@findex easy-mmode-define-minor-mode
@item (:eval @var{form})
A list whose first element is the symbol @code{:eval} says to evaluate
-@var{form}, and use the result as a string to display.
+@var{form}, and use the result as a string to display. Make sure this
+evaluation cannot load any files, as doing so could cause infinite
+recursion.
@item (:propertize @var{elt} @var{props}@dots{})
A list whose first element is the symbol @code{:propertize} says to
A list whose first element is an integer specifies truncation or
padding of the results of @var{rest}. The remaining elements
@var{rest} are processed recursively as mode-line constructs and
-concatenated together. Then the result is space filled (if
-@var{width} is positive) or truncated (to @minus{}@var{width} columns,
-if @var{width} is negative) on the right.
+concatenated together. When @var{width} is positive, the result is
+space filled on the right if its width is less than @var{width}. When
+@var{width} is negative, the result is truncated on the right to
+@minus{}@var{width} columns if its width exceeds @minus{}@var{width}.
For example, the usual way to show what percentage of a buffer is above
the top of the window is to use a list like this: @code{(-3 "%p")}.
@end defvar
@defvar minor-mode-alist
+@anchor{Definition of minor-mode-alist}
This variable holds an association list whose elements specify how the
mode line should indicate that a minor mode is active. Each element of
the @code{minor-mode-alist} should be a two-element list:
The following table lists the recognized @code{%}-constructs and what
they mean. In any construct except @samp{%%}, you can add a decimal
-integer after the @samp{%} to specify how many characters to display.
+integer after the @samp{%} to specify a minimum field width. If the
+width is less, the field is padded with spaces to the right.
@table @code
@item %b
Certain text properties are meaningful in the
mode line. The @code{face} property affects the appearance of text; the
-@code{help-echo} property associate help strings with the text, and
+@code{help-echo} property associates help strings with the text, and
@code{local-map} can make the text mouse-sensitive.
There are four ways to specify text properties for text in the mode
You can use the function @code{format-mode-line} to compute
the text that would appear in a mode line or header line
-based on certain mode-line specification.
+based on a certain mode-line specification.
@defun format-mode-line format &optional face window buffer
This function formats a line of text according to @var{format} as if
for which no @code{face} property is specified gets a default
value which is usually @var{face}. (If @var{face} is @code{t},
that stands for either @code{mode-line} if @var{window} is selected,
-otherwise @code{mode-line-inactive}.)
+otherwise @code{mode-line-inactive}. If @var{face} is @code{nil} or
+omitted, that stands for no face property.)
However, if @var{face} is an integer, the value has no text properties.
HCoop / bpt / emacs.git / blobdiff