[Rd] V2.9.0 changes [Sec=Unclassified]

[Martin Maechler]

>>>>> "TR" == Troy Robertson <Troy.Robertson at aad.gov.au>
>>>>>     on Wed, 24 Jun 2009 16:35:29 +1000 writes:

    TR> Yes, I had looked at R.oo, S4 and proto before beginning coding. I had initially assumed that S4 was an enhancement of or replacement to R.oo that was implemented at a lower level and had decided to go with the 'future' of OO in R.
    TR> These assumptions were not necessarily correct.

>From the view of the R core team,  
S4  *is* ``the future of OO in R''

But then, as professional statisticians, we should consider the
famous
   >>> Prediction is very difficult, especially about the future <<
attributed to Physics Nobel Prize winner Niels Bohr.

---

Martin Maechler, ETH Zurich & R-core


    TR> Troy

    TR> Troy Robertson
    TR> Database and Computing Support Provider
    TR> Southern Ocean Ecosystems, ERM/Fish
    TR> Australian Antarctic Division
    TR> Channel Highway, Kingston 7050
    TR> PH: 03 62323571
    TR> Troy.Robertson at aad.gov.au


    >> -----Original Message-----
    >> From: Antonio, Fabio Di Narzo [mailto:antonio.fabio at gmail.com]
    >> Sent: Tuesday, 23 June 2009 6:22 PM
    >> To: Troy Robertson
    >> Cc: r-devel at R-project.org
    >> Subject: Re: [Rd] V2.9.0 changes [Sec=Unclassified]
    >> 
    >> Not a direct answer to your question, but...
    >> You might consider using the R.oo package, from H. Bengtsson. It's
    >> very stable, written in pure R, and cleanly allows you to do
    >> pass-by-reference OO programming, with no tricks.
    >> 
    >> HTH,
    >> af
    >> 
    >> 2009/6/23 Troy Robertson <Troy.Robertson at aad.gov.au>:
    >> > Hi all,
    >> >
    >> >
    >> >
    >> > Prefix: I am a frustrated Java coder in R.
    >> >
    >> >
    >> >
    >> > I am coding a medium sized ecosystem modelling program in R.  I have
    >> changed to using S4 objects and it has cost me an order of magnitude in
    >> execution speed over the functional model.  I cannot afford this penalty
    >> and have found that it is the result of all the passing-by-value of
    >> objects.
    >> >
    >> >
    >> >
    >> > I see that you can now safely inherit from environment in V2.9.0.
    >> >
    >> > That got me all excited that I would now be able to pass objects by
    >> reference.
    >> >
    >> >
    >> >
    >> > But...
    >> >
    >> > That doesn't seem to be the case.
    >> >
    >> > It only seem that passing an environment which holds the object allows
    >> for pass-by-reference and that passing an object which inherits from
    >> environment doesn't.
    >> >
    >> > Why is this the case, either an object inherits the properties of its
    >> parent or it doesn't.
    >> >
    >> > Has anyone else had a play with this?  Or have I got it all wrong.
    >> >
    >> >
    >> >
    >> > I tried the below:
    >> >
    >> > ------------------------------------------------------------------------
    >> -----------------
    >> >
    >> > setClass('foo', representation=representation(stuff='list',
    >> bar='numeric'),
    >> >
    >> >                     prototype=list(stuff=list(), bar=0),
    >> >
    >> >                     contains='.environment')
    >> >
    >> >
    >> >
    >> > setGeneric('doit', function(.Object, newfoo='environment')
    >> standardGeneric('doit'))
    >> >
    >> >
    >> >
    >> > setMethod('doit', 'foo', function(.Object, newfoo){newfoo at bar <- 10})
    >> >
    >> >
    >> >
    >> > z <- new('foo')
    >> >
    >> >
    >> >
    >> > z at stuff$x <- new('foo')
    >> >
    >> >
    >> >
    >> > doit(z,z at stuff$x)
    >> >
    >> >
    >> >
    >> > z at stuff$x at bar
    >> >
    >> >
    >> >
    >> > [1] 0
    >> >
    >> > ------------------------------------------------------------------------
    >> ------------------
    >> >
    >> >
    >> >
    >> > Can anyone help with a better way of doing this.
    >> >
    >> > I'm trying to avoid all the indirection of packing and unpacking
    >> environments for passing.
    >> >
    >> >
    >> >
    >> >
    >> >
    >> > Thanks heaps
    >> >
    >> > Troy
    >> >

    ..............


    >> --
    >> Antonio, Fabio Di Narzo
    >> Ph.D. student at
    >> Department of Statistical Sciences
    >> University of Bologna, Italy
    TR> ___________________________________________________________________________