"with" doesn't work with names with blanks

On 5/1/22 2:51 PM, Duncan Murdoch wrote:

On 01/05/2022 3:41 p.m., Spencer Graves wrote:

Hello, All:


 ????? Column names in a data.frame are not supposed to have trailing
blanks.? However, a CRAN package created one, which threw an error with
"with".? Consider the following example:


 ? > (tst <- data.frame(1))
 ??? X1
1? 1
 ? > names(tst) <- 'x '
 ? > tst$x
[1] 1
 ? > with(tst, x)
Error in eval(substitute(expr), data, enclos = parent.frame()) :

    object 'x' not found>>

 ????? I think it's interesting that "tst$x" works, but "with(txt, x)".


 ????? Comments?

tst$x works because of partial name matching.? (That leniency is one of
the reasons for advice to avoid using $ in programs.)? It would be chaos
if with() used partial name matching.

You can use

with(txt, `x `)

to include the space in the name.

but to use that, I have to KNOW that the name is `x `, not `x`.  It took
me a while to identify that as the source of the problem:  What I saw
was that "with(tst

	  And thanks for the reminder that you recommend avoiding use of "$".


	  sg


p.s.  After I found the problem, I fixed it using
names(x) <- tis::stripBlanks(names(x))

Duncan Murdoch

 ????? It's not a major problem, though it took me a while to
diagnose.? (I
reported it to the maintainer of the package that returned a data.frame
with names with trailing blanks.)


 ????? Thanks, for all your work in maintaining and upgrading R -- and in
responding to emails from this list.


 ????? Spencer Graves


 ? > sessionInfo()
R version 4.2.0 (2022-04-22)
Platform: x86_64-apple-darwin17.0 (64-bit)
Running under: macOS Big Sur 11.6.5

Matrix products: default
LAPACK:
/Library/Frameworks/R.framework/Versions/4.2/Resources/lib/libRlapack.dylib


locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8

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

loaded via a namespace (and not attached):
[1] compiler_4.2.0 tools_4.2.0
 ? >