[R] RGui: windows-record and command history

[Duncan Murdoch]

On 3/23/2006 10:46 AM, Gabor Grothendieck wrote:
> On 3/23/06, Duncan Murdoch <murdoch at stats.uwo.ca> wrote:
>> On 3/23/2006 10:29 AM, Gabor Grothendieck wrote:
>> > On 3/23/06, Duncan Murdoch <murdoch at stats.uwo.ca> wrote:
>> >> On 3/23/2006 7:35 AM, Thomas Steiner wrote:
>> >> > a) How can I set the recording of all windows()-history forever to
>> >> > "true"? I want something like windows(record = TRUE) but not just for
>> >> > the window that opens then, but for all windows I will open ever.
>> >>
>> >> options(graphics.record=TRUE)
>> >>
>> >> will make that happen for the rest of the session.  To really make it
>> >> happen forever, you need to put this line in your Rprofile (see
>> >> ?Rprofile for where that comes from).
>> >>
>> >> Watch out though:  the graphics history is stored in your current
>> >> workspace in memory, and it can get big.  You might find you're running
>> >> out of memory if you store everything, and you'll find your .RData files
>> >> quite large if you save your workspace.
>> >>
>> >> On my todo list (but not for 2.3.0) is the possibility of setting a
>> >> default history length, perhaps defaulting to saving the last 2 or 3
>> >> pages.
>> >
>> > Would it be feasible to have history on disk or perhaps the last
>> > m in memory and the last n (possibly Inf) on disk?
>>
>> The history is just another R object.  Saving big R objects on disk
>> might be desirable, but it would be a big change, so I'd call it
>> infeasible.  I wouldn't want to get into special-casing this particular
>> R object:  that way lies madness.
>>
>> However, since it is just an R object, it's available for R code to work
>> with, so someone who was interested in doing this could write a
>> contributed package that did it.
> 
> Are there R-level facilities to manipulate the history, not
> just the top?

Sure, it's a regular R object. You will need to read the source to know 
how to interpret it, and since it's undocumented there's a risk of 
changes in future R versions, but it's not very complicated.  See my 
message to Peter.

Duncan Murdoch