(Character Type): Clarify prev. change.

[gnu-emacs] / lispref / objects.texi

diff --git a/lispref/objects.texi b/lispref/objects.texi
index fcfad022dd054e7f33fca5e8f00e03238323fbe8..b721809d18b75143be08e526ec90654cee929c59 100644 (file)
--- a/lispref/objects.texi
+++ b/lispref/objects.texi
@@ -1,7 +1,7 @@
 @c -*-texinfo-*-
 @c This is part of the GNU Emacs Lisp Reference Manual.
 @c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1998, 1999, 2002, 2003,
-@c   2004, 2005 Free Software Foundation, Inc.
+@c   2004, 2005, 2006 Free Software Foundation, Inc.
 @c See the file elisp.texi for copying conditions.
 @setfilename ../info/objects
 @node Lisp Data Types, Numbers, Introduction, Top
@@ -291,7 +291,8 @@ you @emph{must} use a second @samp{\} to quote it: @samp{?\\}.
 vertical tab, formfeed, space, return, del, and escape as @samp{?\a},
 @samp{?\b}, @samp{?\t}, @samp{?\n}, @samp{?\v}, @samp{?\f},
 @samp{?\s}, @samp{?\r}, @samp{?\d}, and @samp{?\e}, respectively.
-Thus,
+(@samp{?\s} followed by a dash has a different meaning---it applies
+the ``super'' modifier to the following character.)  Thus,
 
 @example
 ?\a @result{} 7                 ; @r{control-g, @kbd{C-g}}
@@ -311,7 +312,7 @@ Thus,
   These sequences which start with backslash are also known as
 @dfn{escape sequences}, because backslash plays the role of an
 ``escape character''; this terminology has nothing to do with the
-character @key{ESC}.  @samp{\s} is meant for use only in character
+character @key{ESC}.  @samp{\s} is meant for use in character
 constants; in string constants, just write the space.
 
 @cindex control characters
@@ -430,6 +431,19 @@ Numerically, the
 bit values are 2**22 for alt, 2**23 for super and 2**24 for hyper.
 @end ifnottex
 
+@cindex unicode character escape
+  Emacs provides a syntax for specifying characters by their Unicode
+code points.  @code{?\u@var{nnnn}} represents a character that maps to
+the Unicode code point @samp{U+@var{nnnn}}.  There is a slightly
+different syntax for specifying characters with code points above
+@code{#xFFFF}; @code{\U00@var{nnnnnn}} represents the character whose
+Unicode code point is @samp{U+@var{nnnnnn}}, if such a character
+is supported by Emacs.
+
+  This peculiar and inconvenient syntax was adopted for compatibility
+with other programming languages.  Unlike some other languages, Emacs
+Lisp supports this syntax in only character literals and strings.
+
 @cindex @samp{\} in character constant
 @cindex backslash in character constant
 @cindex octal character code
@@ -999,6 +1013,9 @@ this produces a unibyte string.  However, using any hex escape in a
 string (even for an @acronym{ASCII} character) forces the string to be
 multibyte.
 
+  You can also specify characters in a string by their numeric values
+in Unicode, using @samp{\u} and @samp{\U} (@pxref{Character Type}).
+
   @xref{Text Representations}, for more information about the two
 text representations.
 
@@ -1778,6 +1795,12 @@ with references to further information.
 
 @item windowp
 @xref{Basic Windows, windowp}.
+
+@item booleanp
+@xref{nil and t, booleanp}.
+
+@item string-or-null-p
+@xref{Predicates for Strings, string-or-null-p}.
 @end table
 
   The most general way to check the type of an object is to call the