From wolski at molgen.mpg.de  Tue Sep 14 22:34:18 2004
From: wolski at molgen.mpg.de (Wolski)
Date: Tue Sep 14 22:34:28 2004
Subject: [Rd] prototype in setClass.
Message-ID: <200409142234180547.08111512@mail.math.fu-berlin.de>

Hi!

To specify a prototype in the setClass declaration is a great feature.
But prototype seems no to work for slots of the "super" class.
eg. The following code is declaring first the super class "List".  This class has a slot "content". 
The class "AtomList" inherits from it and I would like to set content="Atom" by prototype(content="Atom").
But after new("AtomList") is called the slot content is empty as you can see running the code below.

setClass("List"
         ,representation(
                         uniq="logical"
                         ,content="character"                           ##### would like to set this when declaring the inheriting class.
                         ,names="character") 
         ,contains="list"
         ,prototype(uniq=FALSE)
         )


setClass("AtomList"
         ,contains="List"
         ,prototype(content="Atom")                                ## would like to specify this
         )

new("AtomList")


An object of class "AtomList"
list()
Slot "uniq":
[1] FALSE

Slot "content":
character(0)                                                            #######<-still not specified even if provided in prototype.

Slot "names":
character(0)


Version:

R : Copyright 2004, The R Foundation for Statistical Computing
Version 2.0.0 alpha (2004-09-14), ISBN 3-900051-07-0
or
R1.9.1 patched.

/E


[Rd] prototype in setClass.
Wolski