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[bpt/emacs.git] / doc / lispref / symbols.texi

diff --git a/doc/lispref/symbols.texi b/doc/lispref/symbols.texi
index 08f7d7f..866a63c 100644 (file)
--- a/doc/lispref/symbols.texi
+++ b/doc/lispref/symbols.texi
@@ -1,7 +1,6 @@
 @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,
-@c   2002, 2003, 2004, 2005, 2006, 2007  Free Software Foundation, Inc.
+@c Copyright (C) 1990-1995, 1998-1999, 2001-2012  Free Software Foundation, Inc.
 @c See the file elisp.texi for copying conditions.
 @setfilename ../../info/symbols
 @node Symbols, Evaluation, Hash Tables, Top
@@ -383,7 +382,7 @@ See @code{documentation} in @ref{Accessing Documentation}, for another
 example using @code{mapatoms}.
 @end defun
 
-@defun unintern symbol &optional obarray
+@defun unintern symbol obarray
 This function deletes @var{symbol} from the obarray @var{obarray}.  If
 @code{symbol} is not actually in the obarray, @code{unintern} does
 nothing.  If @var{obarray} is @code{nil}, the current obarray is used.
@@ -403,15 +402,17 @@ it returns @code{nil}.
 @cindex plist
 
   A @dfn{property list} (@dfn{plist} for short) is a list of paired
-elements stored in the property list cell of a symbol.  Each of the
-pairs associates a property name (usually a symbol) with a property or
-value.  Property lists are generally used to record information about a
-symbol, such as its documentation as a variable, the name of the file
-where it was defined, or perhaps even the grammatical class of the
-symbol (representing a word) in a language-understanding system.
+elements.  Each of the pairs associates a property name (usually a
+symbol) with a property or value.
 
-  Character positions in a string or buffer can also have property lists.
-@xref{Text Properties}.
+  Every symbol has a cell that stores a property list (@pxref{Symbol
+Components}).  This property list is used to record information about
+the symbol, such as its variable documentation and the name of the
+file where it was defined.
+
+  Property lists can also be used in other contexts.  For instance,
+you can assign property lists to character positions in a string or
+buffer.  @xref{Text Properties}.
 
   The property names and values in a property list can be any Lisp
 objects, but the names are usually symbols.  Property list functions
@@ -529,22 +530,18 @@ The @code{put} function returns @var{value}.
 that are stored in places other than symbols:
 
 @defun plist-get plist property
-This returns the value of the @var{property} property
-stored in the property list @var{plist}.  For example,
+This returns the value of the @var{property} property stored in the
+property list @var{plist}.  It accepts a malformed @var{plist}
+argument.  If @var{property} is not found in the @var{plist}, it
+returns @code{nil}.  For example,
 
 @example
 (plist-get '(foo 4) 'foo)
      @result{} 4
 (plist-get '(foo 4 bad) 'foo)
      @result{} 4
-(plist-get '(foo 4 bad) 'bar)
-     @result{} @code{wrong-type-argument} error
-@end example
-
-It accepts a malformed @var{plist} argument and always returns @code{nil}
-if @var{property} is not found in the @var{plist}.  For example,
-
-@example
+(plist-get '(foo 4 bad) 'bad)
+     @result{} nil
 (plist-get '(foo 4 bad) 'bar)
      @result{} nil
 @end example
@@ -592,7 +589,3 @@ between a missing property and a property with the value @code{nil}.
 The value is actually the tail of @var{plist} whose @code{car} is
 @var{property}.
 @end defun
-
-@ignore
-   arch-tag: 8750b7d2-de4c-4923-809a-d35fc39fd8ce
-@end ignore