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Omit unnecessary history from Lisp intro

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* doc/lispintro/emacs-lisp-intro.texi (Review, Digression into C)
(Conclusion): Reword so as not to talk about earlier versions
of Emacs in what should be an intro.
This commit is contained in:
Paul Eggert 2016-01-31 17:31:23 -08:00
parent 2fbd1dabeb
commit 43cb9f8ff3
1 changed files with 10 additions and 34 deletions
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doc/lispintro/emacs-lisp-intro.texi
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@ -4309,38 +4309,18 @@ 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
as follows. (It is slightly more complex now that it seeks the first
non-whitespace character rather than the first visible character.)
For example, in Emacs the function definition of
@code{dired-unmark-all-marks} is as follows.
@smallexample
@group
(defun back-to-indentation ()
"Move point to first visible character on line."
(defun dired-unmark-all-marks ()
"Remove all marks from all files in the Dired buffer."
(interactive)
(beginning-of-line 1)
(skip-chars-forward " \t"))
(dired-unmark-all-files ?\r))
@end group
@end smallexample
@ignore
In GNU Emacs 22,
(defun backward-to-indentation (&optional arg)
"Move backward ARG lines and position at first nonblank character."
(interactive "p")
(forward-line (- (or arg 1)))
(skip-chars-forward " \t"))
(defun back-to-indentation ()
"Move point to the first non-whitespace character on this line."
(interactive)
(beginning-of-line 1)
(skip-syntax-forward " " (line-end-position))
;; Move back over chars that have whitespace syntax but have the p flag.
(backward-prefix-chars))
@end ignore
@item interactive
Declare to the interpreter that the function can be used
interactively. This special form may be followed by a string with one
@ -9123,13 +9103,12 @@ deleted@footnote{More precisely, and requiring more expert knowledge
to understand, the two integers are of type @code{Lisp_Object}, which can
also be a C union instead of an integer type.}.
In early versions of Emacs, these two numbers were thirty-two bits
long, but the code is slowly being generalized to handle other
lengths. Three of the available bits are used to specify the type of
information; the remaining bits are used as content.
Integer widths depend on the machine, and are typically 32 or 64 bits.
A few of the bits are used to specify the type of information; the
remaining bits are used as content.
@samp{XINT} is a C macro that extracts the relevant number from the
longer collection of bits; the three other bits are discarded.
longer collection of bits; the type bits are discarded.
@need 800
The command in @code{delete-and-extract-region} looks like this:
@ -18724,10 +18703,7 @@ Even though it is short, @code{split-line} contains expressions
we have not studied: @code{skip-chars-forward}, @code{indent-to},
@code{current-column} and @code{insert-and-inherit}.
Consider the @code{skip-chars-forward} function. (It is part of the
function definition for @code{back-to-indentation}, which is shown in
@ref{Review, , Review}.)
Consider the @code{skip-chars-forward} function.
In GNU Emacs, you can find out more about @code{skip-chars-forward} by
typing @kbd{C-h f} (@code{describe-function}) and the name of the
function. This gives you the function documentation.