ripley@stats.ox.ac.uk
2003-Oct-18 17:04 UTC
[Rd] Recursive indexing can cause R-1.8.0 (and R-1.7.1) to (PR#4647)
On Thu, 9 Oct 2003 anaximander@gmx.de wrote:> Recursive indexing can cause R-1.8.0 (and R-1.7.1) to segment fault > > First of all, many thanks to the R team!! > R is really a software for everyday work. > Yes, I've found a fault, but I hope it's not just faultfinding ;-) > > In the NEWS file of R-1.8.0, first printed in R NEWS 1.7.1, > there was given a promise: [ 1 ] > o Recursive indexing of lists is allowed, so x[[c(4,2)]] is > shorthand for x[[4]][[2]] etc. (Wishlist PR#1588) > > That's not fulfilled in all cases, although there was already a > code correction in R-1.8.0: [ 2 ] > o Recursive indexing of lists had too little error-checking. > (related to PR#3324)That's not a code correction, that's catching unanticipated user errors. This report is also user error which is not always caught. However, please don't say that something has `not been fulfilled' when it works exactly as documented but punishes misuse too severely. It really is hard to anticipate just how silly users can be.> Of coarse, R is not intended to be an ingenious data base program, > which should be able to handle, let's say, complicated requests > like they are possible in SQL-language. > > On the other side, lists are becoming more and more important in R, > so there *should* be a convenient way to deal with nested lists, shan't it? > Sure, all of us can avoid such lists in our own data, but we often > have to use data files from other people with *have* a nested structure. > (Thats the way I discovered this error.)> Perhaps we can find a fair compromise?Yes, would you please not making sweeping statements about R's abilities based on its not failing to cope with your own particular errors? It did report a correct error message at least once! -- Brian D. Ripley, ripley@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