[R-pkg-devel] [External] [External] RcmdrPlugin.HH_1.1-48.tar.gz

[Duncan Murdoch]

On 07/03/2024 4:16 a.m., Ivan Krylov wrote:
> On Wed, 6 Mar 2024 13:46:55 -0500
> Duncan Murdoch <murdoch.duncan using gmail.com> wrote:
> 
>> is this just a more or less harmless error, thinking that
>> the dot needs escaping
> 
> I think it's this one. You are absolutely right that the dot doesn't
> need escaping in either TRE (which is what's used inside exportPattern)
> or PCRE. In PRCE, this regular expression would have worked as intended:
> 
> # We do match backslashes by mistake.
> grepl('[\\.]', '\\')
> # [1] TRUE
> 
> # In PCRE, this wouldn't have been a mistake.
> grepl('[\\.]', c('\\', '.'), perl = TRUE)
> # [1] FALSE TRUE
> 

Thanks, I didn't realize that escaping in PCRE was optional.

So the default exportPattern line could be

   exportPattern("^[^.]")

and it would work even if things were changed so that PCRE was used 
instead of TRE.

Duncan Murdoch