rm() deletes 'c' if c('a','b') is the argument (PR#9399)

Full_Name: Lixin Han
Version: 2.4.0
OS: Windows 2000
Submission from: (NULL) (155.94.110.222)


A character vector c('a','b') is supplied to rm().  As a result, 'c' is deleted
unintentionally.

a <- 1:5
b <- 'abc'
c <- letters
ls()

[1] "a" "b" "c"

rm(c('a','b'))
ls()

character(0)