From jmc@research.bell-labs.com  Fri Nov 30 15:12:15 2001
From: jmc@research.bell-labs.com (John Chambers)
Date: Fri, 30 Nov 2001 10:12:15 -0500
Subject: [Rd] New version of methods package
Message-ID: <3C07A1CF.36F9C171@research.bell-labs.com>

A new version of the package has been committed to the r-devel branch.

There are a lot of changes, mostly non-visible, many of those to tighten
up some possible problems.  For example, slot assignment now checks the
validity of the value being assigned, and basic classes cannot be
overriden.

There is a version of the promptClass function by Vince Carey, to
produce shell of documentation for a class.  (There is also a
promptMethods function to do the same for methods.)  One point to note
(it's a difference from Vince's original version) is that promptClass
and promptMethods produce alias's specialized for class and method
documentation.

For example, if you do promptClass("track"), the resulting file is
designed to produce help if the user types
  class?track
(In particular, this does not overwrite ordinary documentation for topic
"track".)

There is also some added general documentation on how things work; see
?Methods.  This will grow.

Also, the new version has a trial implementation of "congruent
arguments" for methods a la Dylan.  You can provide a method with only a
subset of the arguments of the generic.  The implication is that the
method is to be applied only if the omitted arguments are missing in the
actual call.  This notion is experimental (and not part of the API in
Programming with Data); we'll see if it works out.

John

-- 
John M. Chambers                  jmc@bell-labs.com
Bell Labs, Lucent Technologies    office: (908)582-2681
700 Mountain Avenue, Room 2C-282  fax:    (908)582-3340
Murray Hill, NJ  07974            web: http://www.cs.bell-labs.com/~jmc
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !)  To: r-devel-request@stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._


[Rd] New version of methods package
John Chambers