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[Emacs-diffs] /srv/bzr/emacs/trunk r99608: Update Lispref for 30-bit int
|
From: |
Glenn Morris |
|
Subject: |
[Emacs-diffs] /srv/bzr/emacs/trunk r99608: Update Lispref for 30-bit integers. |
|
Date: |
Tue, 02 Mar 2010 19:50:15 -0800 |
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User-agent: |
Bazaar (2.0.3) |
------------------------------------------------------------
revno: 99608
committer: Glenn Morris <address@hidden>
branch nick: trunk
timestamp: Tue 2010-03-02 19:50:15 -0800
message:
Update Lispref for 30-bit integers.
* numbers.texi (Integer Basics, Bitwise Operations):
* objects.texi (Integer Type): Update for integers now being 30-bit.
modified:
doc/lispref/ChangeLog
doc/lispref/numbers.texi
doc/lispref/objects.texi
=== modified file 'doc/lispref/ChangeLog'
--- a/doc/lispref/ChangeLog 2010-02-27 15:18:07 +0000
+++ b/doc/lispref/ChangeLog 2010-03-03 03:50:15 +0000
@@ -1,3 +1,8 @@
+2010-03-03 Glenn Morris <address@hidden>
+
+ * numbers.texi (Integer Basics, Bitwise Operations):
+ * objects.texi (Integer Type): Update for integers now being 30-bit.
+
2010-02-27 Chong Yidong <address@hidden>
* display.texi (Low-Level Font): Document :otf font-spec property.
=== modified file 'doc/lispref/numbers.texi'
--- a/doc/lispref/numbers.texi 2010-01-13 08:35:10 +0000
+++ b/doc/lispref/numbers.texi 2010-03-03 03:50:15 +0000
@@ -1,7 +1,8 @@
@c -*-texinfo-*-
@c This is part of the GNU Emacs Lisp Reference Manual.
@c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1998, 1999, 2001,
address@hidden 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free
Software Foundation, Inc.
address@hidden 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
address@hidden Free Software Foundation, Inc.
@c See the file elisp.texi for copying conditions.
@setfilename ../../info/numbers
@node Numbers, Strings and Characters, Lisp Data Types, Top
@@ -36,22 +37,22 @@
@section Integer Basics
The range of values for an integer depends on the machine. The
-minimum range is @minus{}268435456 to 268435455 (29 bits; i.e.,
+minimum range is @minus{}536870912 to 536870911 (30 bits; i.e.,
@ifnottex
--2**28
+-2**29
@end ifnottex
@tex
address@hidden
address@hidden
@end tex
to
@ifnottex
-2**28 - 1),
+2**29 - 1),
@end ifnottex
@tex
address@hidden),
address@hidden),
@end tex
but some machines may provide a wider range. Many examples in this
-chapter assume an integer has 29 bits.
+chapter assume an integer has 30 bits.
@cindex overflow
The Lisp reader reads an integer as a sequence of digits with optional
@@ -62,7 +63,7 @@
1. ; @r{The integer 1.}
+1 ; @r{Also the integer 1.}
-1 ; @r{The integer @minus{}1.}
- 536870913 ; @r{Also the integer 1, due to overflow.}
+ 1073741825 ; @r{Also the integer 1, due to overflow.}
0 ; @r{The integer 0.}
-0 ; @r{The integer 0.}
@end example
@@ -93,10 +94,10 @@
bitwise operators (@pxref{Bitwise Operations}), it is often helpful to
view the numbers in their binary form.
- In 29-bit binary, the decimal integer 5 looks like this:
+ In 30-bit binary, the decimal integer 5 looks like this:
@example
-0 0000 0000 0000 0000 0000 0000 0101
+00 0000 0000 0000 0000 0000 0000 0101
@end example
@noindent
@@ -106,12 +107,12 @@
The integer @minus{}1 looks like this:
@example
-1 1111 1111 1111 1111 1111 1111 1111
+11 1111 1111 1111 1111 1111 1111 1111
@end example
@noindent
@cindex two's complement
address@hidden is represented as 29 ones. (This is called @dfn{two's
address@hidden is represented as 30 ones. (This is called @dfn{two's
complement} notation.)
The negative integer, @minus{}5, is creating by subtracting 4 from
@@ -119,24 +120,24 @@
@minus{}5 looks like this:
@example
-1 1111 1111 1111 1111 1111 1111 1011
+11 1111 1111 1111 1111 1111 1111 1011
@end example
- In this implementation, the largest 29-bit binary integer value is
-268,435,455 in decimal. In binary, it looks like this:
+ In this implementation, the largest 30-bit binary integer value is
+536,870,911 in decimal. In binary, it looks like this:
@example
-0 1111 1111 1111 1111 1111 1111 1111
+01 1111 1111 1111 1111 1111 1111 1111
@end example
Since the arithmetic functions do not check whether integers go
-outside their range, when you add 1 to 268,435,455, the value is the
-negative integer @minus{}268,435,456:
+outside their range, when you add 1 to 536,870,911, the value is the
+negative integer @minus{}536,870,912:
@example
-(+ 1 268435455)
- @result{} -268435456
- @result{} 1 0000 0000 0000 0000 0000 0000 0000
+(+ 1 536870911)
+ @result{} -536870912
+ @result{} 10 0000 0000 0000 0000 0000 0000 0000
@end example
Many of the functions described in this chapter accept markers for
@@ -820,19 +821,19 @@
The function @code{lsh}, like all Emacs Lisp arithmetic functions, does
not check for overflow, so shifting left can discard significant bits
and change the sign of the number. For example, left shifting
-268,435,455 produces @minus{}2 on a 29-bit machine:
+536,870,911 produces @minus{}2 on a 30-bit machine:
@example
-(lsh 268435455 1) ; @r{left shift}
+(lsh 536870911 1) ; @r{left shift}
@result{} -2
@end example
-In binary, in the 29-bit implementation, the argument looks like this:
+In binary, in the 30-bit implementation, the argument looks like this:
@example
@group
-;; @r{Decimal 268,435,455}
-0 1111 1111 1111 1111 1111 1111 1111
+;; @r{Decimal 536,870,911}
+01 1111 1111 1111 1111 1111 1111 1111
@end group
@end example
@@ -842,7 +843,7 @@
@example
@group
;; @r{Decimal @minus{}2}
-1 1111 1111 1111 1111 1111 1111 1110
+11 1111 1111 1111 1111 1111 1111 1110
@end group
@end example
@end defun
@@ -865,9 +866,9 @@
@group
(ash -6 -1) @result{} -3
;; @r{Decimal @minus{}6 becomes decimal @minus{}3.}
-1 1111 1111 1111 1111 1111 1111 1010
+11 1111 1111 1111 1111 1111 1111 1010
@result{}
-1 1111 1111 1111 1111 1111 1111 1101
+11 1111 1111 1111 1111 1111 1111 1101
@end group
@end example
@@ -876,11 +877,11 @@
@example
@group
-(lsh -6 -1) @result{} 268435453
-;; @r{Decimal @minus{}6 becomes decimal 268,435,453.}
-1 1111 1111 1111 1111 1111 1111 1010
+(lsh -6 -1) @result{} 536870909
+;; @r{Decimal @minus{}6 becomes decimal 536,870,909.}
+11 1111 1111 1111 1111 1111 1111 1010
@result{}
-0 1111 1111 1111 1111 1111 1111 1101
+01 1111 1111 1111 1111 1111 1111 1101
@end group
@end example
@@ -890,34 +891,34 @@
@c with smallbook but not with regular book! --rjc 16mar92
@smallexample
@group
- ; @r{ 29-bit binary values}
+ ; @r{ 30-bit binary values}
-(lsh 5 2) ; 5 = @r{0 0000 0000 0000 0000 0000 0000 0101}
- @result{} 20 ; = @r{0 0000 0000 0000 0000 0000 0001 0100}
+(lsh 5 2) ; 5 = @r{00 0000 0000 0000 0000 0000 0000 0101}
+ @result{} 20 ; = @r{00 0000 0000 0000 0000 0000 0001
0100}
@end group
@group
(ash 5 2)
@result{} 20
-(lsh -5 2) ; -5 = @r{1 1111 1111 1111 1111 1111 1111 1011}
- @result{} -20 ; = @r{1 1111 1111 1111 1111 1111 1110 1100}
+(lsh -5 2) ; -5 = @r{11 1111 1111 1111 1111 1111 1111 1011}
+ @result{} -20 ; = @r{11 1111 1111 1111 1111 1111 1110
1100}
(ash -5 2)
@result{} -20
@end group
@group
-(lsh 5 -2) ; 5 = @r{0 0000 0000 0000 0000 0000 0000 0101}
- @result{} 1 ; = @r{0 0000 0000 0000 0000 0000 0000 0001}
+(lsh 5 -2) ; 5 = @r{00 0000 0000 0000 0000 0000 0000 0101}
+ @result{} 1 ; = @r{00 0000 0000 0000 0000 0000 0000
0001}
@end group
@group
(ash 5 -2)
@result{} 1
@end group
@group
-(lsh -5 -2) ; -5 = @r{1 1111 1111 1111 1111 1111 1111 1011}
- @result{} 134217726 ; = @r{0 0111 1111 1111 1111 1111 1111 1110}
+(lsh -5 -2) ; -5 = @r{11 1111 1111 1111 1111 1111 1111 1011}
+ @result{} 268435454 ; = @r{00 0111 1111 1111 1111 1111 1111
1110}
@end group
@group
-(ash -5 -2) ; -5 = @r{1 1111 1111 1111 1111 1111 1111 1011}
- @result{} -2 ; = @r{1 1111 1111 1111 1111 1111 1111 1110}
+(ash -5 -2) ; -5 = @r{11 1111 1111 1111 1111 1111 1111 1011}
+ @result{} -2 ; = @r{11 1111 1111 1111 1111 1111 1111
1110}
@end group
@end smallexample
@end defun
@@ -952,23 +953,23 @@
@smallexample
@group
- ; @r{ 29-bit binary values}
+ ; @r{ 30-bit binary values}
-(logand 14 13) ; 14 = @r{0 0000 0000 0000 0000 0000 0000 1110}
- ; 13 = @r{0 0000 0000 0000 0000 0000 0000 1101}
- @result{} 12 ; 12 = @r{0 0000 0000 0000 0000 0000 0000 1100}
+(logand 14 13) ; 14 = @r{00 0000 0000 0000 0000 0000 0000 1110}
+ ; 13 = @r{00 0000 0000 0000 0000 0000 0000 1101}
+ @result{} 12 ; 12 = @r{00 0000 0000 0000 0000 0000 0000 1100}
@end group
@group
-(logand 14 13 4) ; 14 = @r{0 0000 0000 0000 0000 0000 0000 1110}
- ; 13 = @r{0 0000 0000 0000 0000 0000 0000 1101}
- ; 4 = @r{0 0000 0000 0000 0000 0000 0000 0100}
- @result{} 4 ; 4 = @r{0 0000 0000 0000 0000 0000 0000 0100}
+(logand 14 13 4) ; 14 = @r{00 0000 0000 0000 0000 0000 0000 1110}
+ ; 13 = @r{00 0000 0000 0000 0000 0000 0000 1101}
+ ; 4 = @r{00 0000 0000 0000 0000 0000 0000 0100}
+ @result{} 4 ; 4 = @r{00 0000 0000 0000 0000 0000 0000 0100}
@end group
@group
(logand)
- @result{} -1 ; -1 = @r{1 1111 1111 1111 1111 1111 1111 1111}
+ @result{} -1 ; -1 = @r{11 1111 1111 1111 1111 1111 1111 1111}
@end group
@end smallexample
@end defun
@@ -982,18 +983,18 @@
@smallexample
@group
- ; @r{ 29-bit binary values}
+ ; @r{ 30-bit binary values}
-(logior 12 5) ; 12 = @r{0 0000 0000 0000 0000 0000 0000 1100}
- ; 5 = @r{0 0000 0000 0000 0000 0000 0000 0101}
- @result{} 13 ; 13 = @r{0 0000 0000 0000 0000 0000 0000 1101}
+(logior 12 5) ; 12 = @r{00 0000 0000 0000 0000 0000 0000 1100}
+ ; 5 = @r{00 0000 0000 0000 0000 0000 0000 0101}
+ @result{} 13 ; 13 = @r{00 0000 0000 0000 0000 0000 0000 1101}
@end group
@group
-(logior 12 5 7) ; 12 = @r{0 0000 0000 0000 0000 0000 0000 1100}
- ; 5 = @r{0 0000 0000 0000 0000 0000 0000 0101}
- ; 7 = @r{0 0000 0000 0000 0000 0000 0000 0111}
- @result{} 15 ; 15 = @r{0 0000 0000 0000 0000 0000 0000 1111}
+(logior 12 5 7) ; 12 = @r{00 0000 0000 0000 0000 0000 0000 1100}
+ ; 5 = @r{00 0000 0000 0000 0000 0000 0000 0101}
+ ; 7 = @r{00 0000 0000 0000 0000 0000 0000 0111}
+ @result{} 15 ; 15 = @r{00 0000 0000 0000 0000 0000 0000 1111}
@end group
@end smallexample
@end defun
@@ -1007,18 +1008,18 @@
@smallexample
@group
- ; @r{ 29-bit binary values}
+ ; @r{ 30-bit binary values}
-(logxor 12 5) ; 12 = @r{0 0000 0000 0000 0000 0000 0000 1100}
- ; 5 = @r{0 0000 0000 0000 0000 0000 0000 0101}
- @result{} 9 ; 9 = @r{0 0000 0000 0000 0000 0000 0000 1001}
+(logxor 12 5) ; 12 = @r{00 0000 0000 0000 0000 0000 0000 1100}
+ ; 5 = @r{00 0000 0000 0000 0000 0000 0000 0101}
+ @result{} 9 ; 9 = @r{00 0000 0000 0000 0000 0000 0000 1001}
@end group
@group
-(logxor 12 5 7) ; 12 = @r{0 0000 0000 0000 0000 0000 0000 1100}
- ; 5 = @r{0 0000 0000 0000 0000 0000 0000 0101}
- ; 7 = @r{0 0000 0000 0000 0000 0000 0000 0111}
- @result{} 14 ; 14 = @r{0 0000 0000 0000 0000 0000 0000 1110}
+(logxor 12 5 7) ; 12 = @r{00 0000 0000 0000 0000 0000 0000 1100}
+ ; 5 = @r{00 0000 0000 0000 0000 0000 0000 0101}
+ ; 7 = @r{00 0000 0000 0000 0000 0000 0000 0111}
+ @result{} 14 ; 14 = @r{00 0000 0000 0000 0000 0000 0000 1110}
@end group
@end smallexample
@end defun
@@ -1031,9 +1032,9 @@
@example
(lognot 5)
@result{} -6
-;; 5 = @r{0 0000 0000 0000 0000 0000 0000 0101}
+;; 5 = @r{00 0000 0000 0000 0000 0000 0000 0101}
;; @r{becomes}
-;; -6 = @r{1 1111 1111 1111 1111 1111 1111 1010}
+;; -6 = @r{11 1111 1111 1111 1111 1111 1111 1010}
@end example
@end defun
=== modified file 'doc/lispref/objects.texi'
--- a/doc/lispref/objects.texi 2010-01-13 08:35:10 +0000
+++ b/doc/lispref/objects.texi 2010-03-03 03:50:15 +0000
@@ -165,24 +165,24 @@
@node Integer Type
@subsection Integer Type
- The range of values for integers in Emacs Lisp is @minus{}268435456 to
-268435455 (29 bits; i.e.,
+ The range of values for integers in Emacs Lisp is @minus{}536870912 to
+536870911 (30 bits; i.e.,
@ifnottex
--2**28
+-2**29
@end ifnottex
@tex
address@hidden
address@hidden
@end tex
to
@ifnottex
-2**28 - 1)
+2**29 - 1)
@end ifnottex
@tex
address@hidden)
address@hidden)
@end tex
on most machines. (Some machines may provide a wider range.) It is
important to note that the Emacs Lisp arithmetic functions do not check
-for overflow. Thus @code{(1+ 268435455)} is @minus{}268435456 on most
+for overflow. Thus @code{(1+ 536870911)} is @minus{}536870912 on most
machines.
The read syntax for integers is a sequence of (base ten) digits with an
@@ -196,7 +196,7 @@
1 ; @r{The integer 1.}
1. ; @r{Also the integer 1.}
+1 ; @r{Also the integer 1.}
-536870913 ; @r{Also the integer 1 on a 29-bit implementation.}
+1073741825 ; @r{Also the integer 1 on a 30-bit implementation.}
@end group
@end example
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