R devel - Jul 1998 - Serious bug in save.image

I am using a  package which tends to crash R, so I have been saving
my work at regular intervals with "save.image()". Unfortunately, this
overwrites .RData with an empty workspace, so when R crashed I lost
my workspace and a day's work.

The problem is easily fixed: "save.image" looks like this

function () 
save(list = ls(), file = ".RData")

The expression "ls()" is evaluated in the calling environment, which
is empty. You need to evaluate it in the global environment, like this:

function () 
save(list = eval(expression(ls()), .GlobalEnv), file = ".RData")

Martyn
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Martyn Plummer <plummer@iarc.fr> writes:
> function () 
> save(list = ls(), file = ".RData")
> 
> The expression "ls()" is evaluated in the calling environment,
which
> is empty. You need to evaluate it in the global environment, like this:
> 
> function () 
> save(list = eval(expression(ls()), .GlobalEnv), file = ".RData")
Ouch! Fixed in my sources. Will get to the prerelease versions after I
squash an elusive memory corruption bug.

Actually, I did you one better:
> save.image
function (f = ".RData") 
eval(substitute(save(list = ls(), file = f)), .GlobalEnv)

so that you can now save the image under a different name.

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
 (*) \(*) -- University of Copenhagen   Denmark      Ph: (+45) 35327918
~~~~~~~~~~ - (p.dalgaard@biostat.ku.dk)             FAX: (+45) 35327907
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