[Rd] Bug in subsetting data frame (PR#13515)

Wacek Kusnierczyk Waclaw.Marcin.Kusnierczyk at idi.ntnu.no
Tue Feb 10 14:34:21 CET 2009


Stavros Macrakis wrote:
> Don't know if this is the problem, but....
>
> It is a bad idea to set data.frame <- xxx since R has a single
> namespace for functions and variables.
>
>   

it doesn't seem to be the problem.

c = c(0)
c
# 0, not the function `c`
c(1)
# 1, not an error from application of 0 to 1

but

c = `list`
c(0)
# list, not a vector
c
# the function `list`, not the value 0


the issue is, if you use a name as an operator, it's the first *function
value*, not just *value*, found on the search path that will be used. 
in the example you referred to, if you assign a non-function value to
data.frame, an attempt to apply data.frame will get the function from
package:base:

data.frame = 0
find('data.frame', mode='function')


vQ



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