[R] New Year Wish List

[Gabor Grothendieck]

Baz <B.Rowlingson <at> lancaster.ac.uk> writes:

: 
: Gabor Grothendieck wrote:
: > Congrats to all those who have contributed to R over the
: > past year.  As with last year, for New Year I would like to
: > list the top 10 features I would like to see in R.   The first 
: > three are the most important.
: 
:   My wish for R is some sort of timestamping on objects, so I know when 
: they were created or modified.
: 
:   This would then enable the creation of a 'make'-like system in R, 
: where the 'target' is some output of an analysis (eg the fit of a linear 
: model) and the dependencies are the input data.
: 
:   For a complex problem, you might have a target that depends on many 
: other things, and you dont want to have to redo expensive operations (eg 
: MCMC runs, large simulations) if nothing that they depend on has 
: changed. The grand idea is to have a single specification of the problem 
: (which would be an R object of class 'make' perhaps) and then you can 
: just do make(foo) to do all the required code to get the result.
: 
:   This might be a very useful method for transferring analyses between 
: people.
: 
:   I did have a hack at putting timestamps on R objects by mucking with 
: the C code that created new objects, and adding an 
: attribute('timestamp'). It superficially worked, but R started to fall 
: to pieces since objects stopped being identical to copies of themselves. 
: Oops. it clearly needs attaching at a lower level, but I'm not sure 
: where or how much of a performance hit it might be.
: 
:   End of wishlist.


Not sure if this is good enough but there have been some attempts
along this line but without modifying R.  One could manually store the
timestamp in an attribute, in a global list with one component per
variable that you want to track or save each variable
manually in an .rda file using that file's stamp.  Its possible
to hide some of it to avoid cluttering your code.  See 
the following:

https://www.stat.math.ethz.ch/pipermail/r-help/2004-October/056969.html
http://maths.newcastle.edu.au/~rking/R/help/03a/6412.html
http://tolstoy.newcastle.edu.au/R/help/04/05/0242.html