@set edition-number 3.10
@set update-date 28 October 2009
+@c FIXME can this be updated? -- xfq
@ignore
## Summary of shell commands to create various output formats:
function is written in Emacs Lisp or C.
@node defun
-@section The @code{defun} Special Form
+@section The @code{defun} Macro
@findex defun
-@cindex Special form of @code{defun}
@cindex @samp{function definition} defined
In Lisp, a symbol such as @code{mark-whole-buffer} has code attached to
it that tells the computer what to do when the function is called.
This code is called the @dfn{function definition} and is created by
evaluating a Lisp expression that starts with the symbol @code{defun}
-(which is an abbreviation for @emph{define function}). Because
-@code{defun} does not evaluate its arguments in the usual way, it is
-called a @dfn{special form}.
+(which is an abbreviation for @emph{define function}).
In subsequent sections, we will look at function definitions from the
Emacs source code, such as @code{mark-whole-buffer}. In this section,
@findex point
@findex mark
-The @code{save-excursion} function is the fourth and final special form
+The @code{save-excursion} function is the third and final special form
that we will discuss in this chapter.
In Emacs Lisp programs used for editing, the @code{save-excursion}
@node Review
@section Review
-In the last few chapters we have introduced a fair number of functions
-and special forms. Here they are described in brief, along with a few
-similar functions that have not been mentioned yet.
+In the last few chapters we have introduced a macro and a fair number
+of functions and special forms. Here they are described in brief,
+along with a few similar functions that have not been mentioned yet.
@table @code
@item eval-last-sexp
current buffer. This command is normally bound to @kbd{C-x C-e}.
@item defun
-Define function. This special form has up to five parts: the name,
-a template for the arguments that will be passed to the function,
-documentation, an optional interactive declaration, and the body of the
-definition.
+Define function. This macro has up to five parts: the name, a
+template for the arguments that will be passed to the function,
+documentation, an optional interactive declaration, and the body of
+the definition.
@need 1250
For example, in an early version of Emacs, the function definition was
@end smallexample
Like all function definitions, this definition has five parts following
-the special form @code{defun}:
+the macro @code{defun}:
@enumerate
@item
not override the existing value. Second, @code{defvar} has a
documentation string.
-(Another special form, @code{defcustom}, is designed for variables
-that people customize. It has more features than @code{defvar}.
-(@xref{defcustom, , Setting Variables with @code{defcustom}}.)
-
@menu
* See variable current value::
* defvar and asterisk::
A function definition provides the blueprints for a robot. When you
install a function definition, that is, when you evaluate a
-@code{defun} special form, you install the necessary equipment to
-build robots. It is as if you were in a factory, setting up an
-assembly line. Robots with the same name are built according to the
-same blueprints. So they have, as it were, the same `model number',
-but a different `serial number'.
+@code{defun} macro, you install the necessary equipment to build
+robots. It is as if you were in a factory, setting up an assembly
+line. Robots with the same name are built according to the same
+blueprints. So they have, as it were, the same `model number', but a
+different `serial number'.
We often say that a recursive function `calls itself'. What we mean
is that the instructions in a recursive function cause the Lisp
file. Indeed, you can write any Lisp expression in your @file{.emacs}
file.)
-The @code{customize} feature depends on the @code{defcustom} special
-form. Although you can use @code{defvar} or @code{setq} for variables
-that users set, the @code{defcustom} special form is designed for the
-job.
+The @code{customize} feature depends on the @code{defcustom} macro.
+Although you can use @code{defvar} or @code{setq} for variables that
+users set, the @code{defcustom} macro is designed for the job.
You can use your knowledge of @code{defvar} for writing the
first three arguments for @code{defcustom}. The first argument to
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