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## emacs-27 4e5ac4b: Reorder discussion of integer basics

 From: Paul Eggert Subject: emacs-27 4e5ac4b: Reorder discussion of integer basics Date: Mon, 17 Feb 2020 16:37:20 -0500 (EST)

```branch: emacs-27
commit 4e5ac4b0c611571d3e7930a27693a3fe03be1f40

Reorder discussion of integer basics

* doc/lispref/numbers.texi (Integer Basics): Put the fixnum/bignum
discussion at the end of the section, not at the start (Bug#39557).
---
doc/lispref/numbers.texi | 77 +++++++++++++++++++++++++-----------------------
1 file changed, 40 insertions(+), 37 deletions(-)

diff --git a/doc/lispref/numbers.texi b/doc/lispref/numbers.texi
index c8941ea..4b9fdf2 100644
--- a/doc/lispref/numbers.texi
+++ b/doc/lispref/numbers.texi
@@ -34,39 +34,6 @@ numbers have a fixed amount of precision.
@node Integer Basics
@section Integer Basics

-  Integers in Emacs Lisp are not limited to the machine word size.
-
-  Under the hood, though, there are two kinds of integers: smaller
-ones, called @dfn{fixnums}, and larger ones, called @dfn{bignums}.
-Some functions in Emacs accept only fixnums.  Also, while fixnums can
-be compared for numeric equality with @code{eq}, bignums require
-more-heavyweight equality predicates like @code{eql} and @code{=}.
-
-  The range of values for bignums is limited by the amount of main
-memory, by machine characteristics such as the size of the word used
-to represent a bignum's exponent, and by the @code{integer-width}
-variable.  These limits are typically much more generous than the
-limits for fixnums.  A bignum is never numerically equal to a fixnum;
-if Emacs computes an integer in fixnum range, it represents the
-integer as a fixnum, not a bignum.
-
-  The range of values for a fixnum depends on the machine.  The
-minimum range is @minus{}536,870,912 to 536,870,911 (30 bits; i.e.,
-@ifnottex
-@minus{}2**29
-@end ifnottex
-@tex
-@math{-2^{29}}
-@end tex
-to
-@ifnottex
-2**29 @minus{} 1),
-@end ifnottex
-@tex
-@math{2^{29}-1}),
-@end tex
-but many machines provide a wider range.
-
of decimal digits with optional initial sign and optional
final period.
@@ -145,6 +112,46 @@ arguments to such functions may be either numbers or
markers, we often
give these arguments the name @var{number-or-marker}.  When the argument
value is a marker, its position value is used and its buffer is ignored.

+  In Emacs Lisp, text characters are represented by integers.  Any
+integer between zero and the value of @code{(max-char)}, inclusive, is
+considered to be valid as a character.  @xref{Character Codes}.
+
+  Integers in Emacs Lisp are not limited to the machine word size.
+Under the hood, though, there are two kinds of integers: smaller ones,
+called @dfn{fixnums}, and larger ones, called @dfn{bignums}.  Although
+Emacs Lisp code ordinarily should not depend on whether an integer is
+a fixnum or a bignum, older Emacs versions support only fixnums, some
+functions in Emacs still accept only fixnums, and older Emacs Lisp
+code may have trouble when given bignums.  For example, while older
+Emacs Lisp code could safely compare integers for numeric equality
+with @code{eq}, the presence of bignums means that equality predicates
+like @code{eql} and @code{=} should now be used to compare integers.
+
+  The range of values for bignums is limited by the amount of main
+memory, by machine characteristics such as the size of the word used
+to represent a bignum's exponent, and by the @code{integer-width}
+variable.  These limits are typically much more generous than the
+limits for fixnums.  A bignum is never numerically equal to a fixnum;
+if Emacs computes an integer in fixnum range, it represents the
+integer as a fixnum, not a bignum.
+
+  The range of values for a fixnum depends on the machine.  The
+minimum range is @minus{}536,870,912 to 536,870,911 (30 bits; i.e.,
+@ifnottex
+@minus{}2**29
+@end ifnottex
+@tex
+@math{-2^{29}}
+@end tex
+to
+@ifnottex
+2**29 @minus{} 1),
+@end ifnottex
+@tex
+@math{2^{29}-1}),
+@end tex
+but many machines provide a wider range.
+
@cindex largest fixnum
@cindex maximum fixnum
@defvar most-positive-fixnum
@@ -207,10 +214,6 @@ Setting this variable to a large number can be costly if a
computation
creates huge integers.
@end defvar

-  In Emacs Lisp, text characters are represented by integers.  Any
-integer between zero and the value of @code{(max-char)}, inclusive, is
-considered to be valid as a character.  @xref{Character Codes}.
-
@node Float Basics
@section Floating-Point Basics

```