R help - Sep 2006 - How to retrieve results of most recent command?

In R, is there an automatic variable that stores the results of the most
recent command or commands?  (I am thinking of a behavior like
Mathematica's % result-history substitution syntax.)


(I am using R 2.3.1 on Linux and R 2.3.1 on Windows XP.)


This is a pretty basic question, so I tried to do an extensive version
of the recommended pre-posting homework.
> help.search('substitution')
failed to turn up anything relevant.  This is more an environmental
question, not an R-language programming question.
> help.search('history')
was interesting, but focused on command history.  'savehistory' appears
to be an atomic function, so the temporary-file manipulation done by
'history' seems required.  Perhaps I could try store the desired line in
a string and then evaluate it, but this method feels terribly clunky.
On the other hand, that may be the price to pay for avoidance of
creeping featurism.

The top 10 RSiteSearch results also focus on saving the command
histories to a file or script.  The 'Emacs Speaks Statistics' (ESS)
package seems to offer shortcuts for command history expansion, but not
results history.  I'm a bit reluctant to start using Emacs again, having
quit it for VI over a decade ago.



212-933-3305 / richard.c.yeh at bankofamerica.com 


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Yeh, Richard C wrote:
> In R, is there an automatic variable that stores the results of the most
> recent command or commands?  (I am thinking of a behavior like
> Mathematica's % result-history substitution syntax.)
> 
Something like .Last.value:

  > x=sqrt(2)
  > .Last.value
  [1] 1.414214

which might get more usage if it was less fiddly to type.


Barry