pattern in history
That's an interesting suggestion, but 1) it is not a good idea to change the order of arguments in a function. 2) is the 'unique' argument useful? I cannot see it being used if there is no pattern search, nor I do see the merit in showing repeated lines if I have subselected. 3) like ls(), testing if 'pattern' were missing or NULL would be a better idea.
On Tue, 11 Apr 2006, Romain Francois wrote:
Hi,
Sometimes I need to consult the history of commands that are matching a
regex, so I modified the utils::history function for that purpose. I
found it useful.
I append the code ( I only added the two lines with #**)
Romain.
history2 <-
function (pattern="", max.show = 25, reverse = FALSE, unique =
pattern!="", ...)
{
file1 <- tempfile("Rrawhist")
savehistory(file1)
rawhist <- scan(file1, what = "", quiet = TRUE, sep = "\n")
rawhist <- rawhist[grep(pattern, rawhist, ...)] #**
if(unique) rawhist <- unique(rawhist) #**
unlink(file1)
nlines <- length(rawhist)
inds <- max(1, nlines - max.show):nlines
if (reverse)
inds <- rev(inds)
file2 <- tempfile("hist")
write(rawhist[inds], file2)
file.show(file2, title = "R History", delete.file = TRUE)
}
Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595