[datatable-help] Bug? removing first column, can remove others ok

[Timothée Carayol]

I have a problem, quite related to the one I was mentioning yesterday
and earlier today; Matthew suggested I ask the list whether anyone
else can reproduce it, or whether it's just my installation. Matthew's
guess is that it's either my installation or anyone with 64-bit linux;
so anyone running 64-bit unix based system is welcome to try the code
below.


This works:

> A <- data.table(V1=1:10, V2=1:10)
> A[, V2:=NULL]
      V1
 [1,]  1
 [2,]  2
 [3,]  3
 [4,]  4
 [5,]  5
 [6,]  6
 [7,]  7
 [8,]  8
 [9,]  9
[10,] 10


But this either crashes R (segfault) or returns the following error
and corrupts the object:

> A[, V1:=NULL]
Error in data.table(lapply(x, function(x) { :
  'translateCharUTF8' must be called on a CHARSXP


The column names are irrelevant; the same error happens if I call them
"a" and "b" (for example).

The problem affects me both under data.table 1.6.3 and 1.6.4.



sessionInfo()
R version 2.13.1 (2011-07-08)
Platform: x86_64-unknown-linux-gnu (64-bit)

locale:
 [1] LC_CTYPE=en_GB.UTF-8       LC_NUMERIC=C
LC_TIME=en_GB.UTF-8        LC_COLLATE=en_GB.UTF-8     LC_MONETARY=C
 [6] LC_MESSAGES=en_GB.UTF-8    LC_PAPER=en_GB.UTF-8       LC_NAME=C
               LC_ADDRESS=C               LC_TELEPHONE=C
[11] LC_MEASUREMENT=en_GB.UTF-8 LC_IDENTIFICATION=C

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base

other attached packages:
[1] data.table_1.6.3


Many thanks
Timothee