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* emacs-lisp-intro.texi (defcustom, defun, simplified-beginning-of-buffer, defvar, Building Robots, Review, save-excursion): defun' and defcustom' are now macros rather than special forms. (Bug#13853)

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@ -1,3 +1,10 @@
2013-04-21 Xue Fuqiao <xfq.free@gmail.com>
* emacs-lisp-intro.texi (defcustom, defun)
(simplified-beginning-of-buffer, defvar, Building Robots, Review)
(save-excursion): `defun' and `defcustom' are now macros rather
than special forms. (Bug#13853)
2013-03-16 Glenn Morris <rgm@gnu.org> 2013-03-16 Glenn Morris <rgm@gnu.org>
* emacs-lisp-intro.texi: Add some stuff specific to www.gnu.org. * emacs-lisp-intro.texi: Add some stuff specific to www.gnu.org.

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doc/lispintro/emacs-lisp-intro.texi
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@ -37,6 +37,7 @@
@set edition-number 3.10 @set edition-number 3.10
@set update-date 28 October 2009 @set update-date 28 October 2009
@c FIXME can this be updated? -- xfq
@ignore @ignore
## Summary of shell commands to create various output formats: ## Summary of shell commands to create various output formats:
@ -3094,18 +3095,15 @@ unless you investigate, you won't know whether an already-written
function is written in Emacs Lisp or C. function is written in Emacs Lisp or C.
@node defun @node defun
@section The @code{defun} Special Form @section The @code{defun} Macro
@findex defun @findex defun
@cindex Special form of @code{defun}
@cindex @samp{function definition} defined @cindex @samp{function definition} defined
In Lisp, a symbol such as @code{mark-whole-buffer} has code attached to 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. 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 This code is called the @dfn{function definition} and is created by
evaluating a Lisp expression that starts with the symbol @code{defun} evaluating a Lisp expression that starts with the symbol @code{defun}
(which is an abbreviation for @emph{define function}). Because (which is an abbreviation for @emph{define function}).
@code{defun} does not evaluate its arguments in the usual way, it is
called a @dfn{special form}.
In subsequent sections, we will look at function definitions from the In subsequent sections, we will look at function definitions from the
Emacs source code, such as @code{mark-whole-buffer}. In this section, Emacs source code, such as @code{mark-whole-buffer}. In this section,
@ -4254,7 +4252,7 @@ On the other hand, this function returns @code{nil} if the test is false.
@findex point @findex point
@findex mark @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. that we will discuss in this chapter.
In Emacs Lisp programs used for editing, the @code{save-excursion} In Emacs Lisp programs used for editing, the @code{save-excursion}
@ -4381,9 +4379,9 @@ within the body of a @code{let} expression. It looks like this:
@node Review @node Review
@section Review @section Review
In the last few chapters we have introduced a fair number of functions In the last few chapters we have introduced a macro and a fair number
and special forms. Here they are described in brief, along with a few of functions and special forms. Here they are described in brief,
similar functions that have not been mentioned yet. along with a few similar functions that have not been mentioned yet.
@table @code @table @code
@item eval-last-sexp @item eval-last-sexp
@ -4393,10 +4391,10 @@ invoked with an argument; in that case, the output is printed in the
current buffer. This command is normally bound to @kbd{C-x C-e}. current buffer. This command is normally bound to @kbd{C-x C-e}.
@item defun @item defun
Define function. This special form has up to five parts: the name, Define function. This macro has up to five parts: the name, a
a template for the arguments that will be passed to the function, template for the arguments that will be passed to the function,
documentation, an optional interactive declaration, and the body of the documentation, an optional interactive declaration, and the body of
definition. the definition.
@need 1250 @need 1250
For example, in an early version of Emacs, the function definition was For example, in an early version of Emacs, the function definition was
@ -4803,7 +4801,7 @@ leave mark at previous position."
@end smallexample @end smallexample
Like all function definitions, this definition has five parts following Like all function definitions, this definition has five parts following
the special form @code{defun}: the macro @code{defun}:
@enumerate @enumerate
@item @item
@ -9293,10 +9291,6 @@ have a value. If the variable already has a value, @code{defvar} does
not override the existing value. Second, @code{defvar} has a not override the existing value. Second, @code{defvar} has a
documentation string. 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 @menu
* See variable current value:: * See variable current value::
* defvar and asterisk:: * defvar and asterisk::
@ -11300,11 +11294,11 @@ Let's expand on the metaphor in which a computer program is a robot.
A function definition provides the blueprints for a robot. When you A function definition provides the blueprints for a robot. When you
install a function definition, that is, when you evaluate a install a function definition, that is, when you evaluate a
@code{defun} special form, you install the necessary equipment to @code{defun} macro, you install the necessary equipment to build
build robots. It is as if you were in a factory, setting up an robots. It is as if you were in a factory, setting up an assembly
assembly line. Robots with the same name are built according to the line. Robots with the same name are built according to the same
same blueprints. So they have, as it were, the same `model number', blueprints. So they have, as it were, the same `model number', but a
but a different `serial number'. different `serial number'.
We often say that a recursive function `calls itself'. What we mean We often say that a recursive function `calls itself'. What we mean
is that the instructions in a recursive function cause the Lisp is that the instructions in a recursive function cause the Lisp
@ -16971,10 +16965,9 @@ definitions; but you can write @code{defuns} in your @file{.emacs}
file. Indeed, you can write any Lisp expression in your @file{.emacs} file. Indeed, you can write any Lisp expression in your @file{.emacs}
file.) file.)
The @code{customize} feature depends on the @code{defcustom} special The @code{customize} feature depends on the @code{defcustom} macro.
form. Although you can use @code{defvar} or @code{setq} for variables Although you can use @code{defvar} or @code{setq} for variables that
that users set, the @code{defcustom} special form is designed for the users set, the @code{defcustom} macro is designed for the job.
job.
You can use your knowledge of @code{defvar} for writing the You can use your knowledge of @code{defvar} for writing the
first three arguments for @code{defcustom}. The first argument to first three arguments for @code{defcustom}. The first argument to