[R] Singleton pattern

[Bryan Hanson]

Since no one else has "bit", I'll take a stab.  I'm an experienced R person, but I've recently been teaching myself objective-c and I've been using singletons quite a bit (and mis-using them quite a bit!).  Not a computer scientist at all.  You've been warned.

I don't think there is a comparable concept in R.  You do have a choice of S3 or S4 classes for your object orientation in R.  S3 is very loose in that you can add to S3 objects readily and abuse them a lot.  There really is no checking of them unless you implement it manually.  S4 objects are much "tighter" and they are less readily modified and are self-checking (I know some will complain about this characterization but  it's approximately correct).  So perhaps you want an S4 object so it's less likely to get mangled, but I doubt there is a way to prevent users from copying it, which would be more along the lines of a singleton.

You can google the archives for some great discussions of S3 vs S4 if that sounds interesting.

Bryan

***********
Bryan Hanson
Professor of Chemistry & Biochemistry
DePauw University

On Mar 16, 2012, at 7:47 AM, David Cassany wrote:

> Hi all,
> 
> I know it may not have much sense thinking about a Singleton Pattern in an
> R application which doesn't use any OOP facilities, however I'm curious to
> know if anybody faced the same issue. I've been googling but using
> "singleton pattern" as a key word leads to typical OOP languages like Java
> or C++ among others.
> 
> So my problem is that I'd like to ensure some very big objects aren't
> copied again and again in some other variables. In the worst case I'll
> check all code by myself to ensure it but in this case the application
> won't force programmers to take it in consideration which is what I am
> really looking for.
> 
> Any advice will be highly appreciated :P
> 
> Thanks!
> -- 
> *David Cassany Viladomat
> Software Developer
> Transmural Biote**ch S.L*
> 
> 	[[alternative HTML version deleted]]
> 
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