From hadley at rice.edu  Wed May 11 23:33:39 2011
From: hadley at rice.edu (Hadley Wickham)
Date: Wed, 11 May 2011 16:33:39 -0500
Subject: [Rd] Reference Classes copy(shallow=FALSE) unexpected behavior.
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> But the general problem is tricky. ?What about reference objects contained
> in attributes or slots of other objects, etc? ?What is ?needed for total
> copying is a switch in the low-level duplication code that says to copy
> reference objects. ?It's also possible that one does NOT want all such
> objects copied.

Good point.  I wonder what other languages do? And in fact, are there
any other languages that mix mutable and non-mutable objects in this
way?

Hadley


-- 
Assistant Professor / Dobelman Family Junior Chair
Department of Statistics / Rice University
http://had.co.nz/



[Rd] Reference Classes copy(shallow=FALSE) unexpected behavior.
Hadley Wickham