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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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Xue Fuqiao 2013-04-21 19:56:28 +08:00
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doc/lispintro/ChangeLog
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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>
* emacs-lisp-intro.texi: Add some stuff specific to www.gnu.org.

47
doc/lispintro/emacs-lisp-intro.texi
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@ -37,6 +37,7 @@
@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:
@ -3094,18 +3095,15 @@ unless you investigate, you won't know whether an already-written
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,
@ -4254,7 +4252,7 @@ On the other hand, this function returns @code{nil} if the test is false.
@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}
@ -4381,9 +4379,9 @@ within the body of a @code{let} expression. It looks like this:
@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
@ -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}.
@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
@ -4803,7 +4801,7 @@ leave mark at previous position."
@end smallexample
Like all function definitions, this definition has five parts following
the special form @code{defun}:
the macro @code{defun}:
@enumerate
@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
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::
@ -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
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
@ -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.)
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