xemacs-beta: man/cl.texi comparison

comparison man/cl.texi @ 412:697ef44129c6 r21-2-14

Import from CVS: tag r21-2-14

author	cvs
date	Mon, 13 Aug 2007 11:20:41 +0200
parents	a86b2b5e0111
children

comparison

equal deleted inserted replaced

-:12e008d41344
+:697ef44129c6
 case, a @samp{*} has been appended to the Common Lisp name to obtain
 the Emacs name:
 @example
 defun*        defsubst*     defmacro*     function*
-member*       assoc*        rassoc*       remove*
+member*       assoc*        rassoc*       get*
-delete*       mapcar*       sort*         floor*
+remove*       delete*       mapcar*       sort*
-ceiling*      truncate*     round*        mod*
+floor*        ceiling*      truncate*     round*
-rem*          random*
+mod*          rem*          random*
 @end example
 Internal function and variable names in the package are prefixed
 by @code{cl-}.  Here is a complete list of functions @emph{not}
 prefixed by @code{cl-} which were not taken from Common Lisp:
 @smallexample
 car                 cdr                 caar .. cddddr
 nth                 rest                first .. tenth
 aref                elt                 nthcdr
 symbol-function     symbol-value        symbol-plist
-get                 getf                gethash
+get                 get*                getf
-subseq
+gethash             subseq
 @end smallexample
 @noindent
 Note that for @code{nthcdr} and @code{getf}, the list argument
 of the function must itself be a valid @var{place} form.  For
 Emacs 19.
 @example
 (declaim (inline foo bar))
 (eval-when (compile load eval) (proclaim '(inline foo bar)))
-(proclaim-inline foo bar)   ; XEmacs only
+(proclaim-inline foo bar)      ; XEmacs only
-(defsubst foo (...) ...)    ; instead of defun; Emacs 19 only
+(defsubst foo (...) ...)       ; instead of defun; Emacs 19 only
 @end example
 @strong{Please note:}  This declaration remains in effect after the
 containing source file is done.  It is correct to use it to
 request that a function you have defined should be inlined,
 @noindent
 This package defines several symbol-related features that were
 missing from Emacs Lisp.
 @menu
-* Property Lists::       `getf', `remf'
+* Property Lists::       `get*', `remprop', `getf', `remf'
 * Creating Symbols::     `gensym', `gentemp'
 @end menu
 @node Property Lists, Creating Symbols, Symbols, Symbols
 @section Property Lists
 @noindent
 These functions augment the standard Emacs Lisp functions @code{get}
-and @code{put} for operating on properties attached to objects.
+and @code{put} for operating on properties attached to symbols.
 There are also functions for working with property lists as
-first-class data structures not attached to particular objects.
+first-class data structures not attached to particular symbols.
+@defun get* symbol property &optional default
+This function is like @code{get}, except that if the property is
+not found, the @var{default} argument provides the return value.
+(The Emacs Lisp @code{get} function always uses @code{nil} as
+the default; this package's @code{get*} is equivalent to Common
+Lisp's @code{get}.)
+The @code{get*} function is @code{setf}-able; when used in this
+fashion, the @var{default} argument is allowed but ignored.
+@end defun
+@defun remprop symbol property
+This function removes the entry for @var{property} from the property
+list of @var{symbol}.  It returns a true value if the property was
+indeed found and removed, or @code{nil} if there was no such property.
+(This function was probably omitted from Emacs originally because,
+since @code{get} did not allow a @var{default}, it was very difficult
+to distinguish between a missing property and a property whose value
+was @code{nil}; thus, setting a property to @code{nil} was close
+enough to @code{remprop} for most purposes.)
+@end defun
 @defun getf place property &optional default
 This function scans the list @var{place} as if it were a property
 list, i.e., a list of alternating property names and values.  If
 an even-numbered element of @var{place} is found which is @code{eq}
 @example
 (put sym prop val)  @equiv{}  (setf (getf (symbol-plist sym) prop) val)
 @end example
-The @code{get} function is also @code{setf}-able.  The fact that
+The @code{get} and @code{get*} functions are also @code{setf}-able.
-@code{default} is ignored can sometimes be useful:
+The fact that @code{default} is ignored can sometimes be useful:
 @example
-(incf (get 'foo 'usage-count 0))
+(incf (get* 'foo 'usage-count 0))
 @end example
 Here, symbol @code{foo}'s @code{usage-count} property is incremented
 if it exists, or set to 1 (an incremented 0) otherwise.
 @code{gethash}.  If @var{key} already exists in the table, the
 corresponding value is changed to the stored value.  If @var{key}
 does not already exist, a new entry is added to the table and the
 table is reallocated to a larger size if necessary.  The @var{default}
 argument is allowed but ignored in this case.  The situation is
-exactly analogous to that of @code{get}; @pxref{Property Lists}.
+exactly analogous to that of @code{get*}; @pxref{Property Lists}.
 @end defun
 @defun remhash key table
 This function removes the entry for @var{key} from @var{table}.
 If an entry was removed, it returns @code{t}.  If @var{key} does
 In Common Lisp, one traditionally uses @code{#'} notation when
 referring to the name of a function.  In Emacs Lisp, it works
 just as well to use a regular quote:
 @example
-(loop for x in y by #'cddr collect (mapcar #'plusp x)) ; Common Lisp
+(loop for x in y by #'cddr collect (mapcar #'plusp x))  ; Common Lisp
-(loop for x in y by 'cddr collect (mapcar 'plusp x))   ; Emacs Lisp
+(loop for x in y by 'cddr collect (mapcar 'plusp x))    ; Emacs Lisp
 @end example
 When @code{#'} introduces a @code{lambda} form, it is best to
 write out @code{(function ...)} longhand in Emacs Lisp.  You can
 use a regular quote, but then the byte-compiler won't know that

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comparison man/cl.texi @ 412:697ef44129c6 r21-2-14