[R] When to quote a package name

[Uwe Ligges]

Muenchen, Robert A (Bob) wrote:
> Dear HelpeRs,
> 
> I'm confused about the role of quotes around package names on the
> library and detach functions. Books on R use both approaches:
> 
> library(Hmisc)
> describe(mydata)
> detach(package:Hmisc)
> 
> and
> 
> library("Hmisc")
> describe(mydata)
> detach("package:Hmisc")
> 
> The help file for detach says "quoted or unquoted" and the help file for
> library says about the package, "the name of a package, given as a name
> or literal character string, or a character string, depending on whether
> character.only is FALSE (default) or TRUE)."
> 
> Are there conditions under which it matters? Which is best?
> 

The cleaner approach is to use quotes. I'd expect

x <- "Hmisc"
library(x)

to install package "Hmisc", but not package "x"...
In fact, it also installs "x" (as documented), unfortunately.

Uwe Ligges



> Thanks,
> Bob
> 
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