don't warn about `[` missing a matching ]

[aavogt]

Code like this doesn't need a matching ]:

map_chr( `[`(2))

My change won't warn about this:

(
[
)

But I think nobody puts [ at the start of the line.

[jalvesaq]

Could you please post an example of code that will be better highlighted if your pull request is merged?

[aavogt]

c('data/b/c', 'data/b2/c') %>%
   strsplit('/') %>%
  map_chr( `[`(2) )

The problem is with .Rmd, not .R. I'm not sure what color the [ should be -- probably it should be the same as %>%. Anyways, the ) is what's annoying me, but fixing the [ might fix the ) too.

[aavogt]

The previous code marked the final ] in xs[[ length(xs) ]] as an error.

[jalvesaq]

The syntax/r.vim has some lines that are not evaluated if the filetype is rmd:

https://github.com/jalvesaq/R-Vim-runtime/blob/master/syntax/r.vim#L235-L239

and

https://github.com/jalvesaq/R-Vim-runtime/blob/master/syntax/r.vim#L311-L313

Could you, please, try removing the condition? That is, syntax/r.vim would be exactly the same for both r and rmd. I know that this will fix the issue, but does it create new problems? We have to try the changes for some time to be sure.

[aavogt]

I've settled on just adding

    syn match rFunction "`\[\+`"

With .Rmd it looks like:

But with .R, the https://github.com/jalvesaq/R-Vim-runtime/blob/master/syntax/r.vim#L311-L313 interferes, leading to:

We can't have https://github.com/jalvesaq/R-Vim-runtime/blob/a9b6ac04a9aea0a369f5e52a9475c71e4ad6adf4/syntax/r.vim#L311-L313 enabled in .Rmd because code blocks start with ```, which matches that pattern. That leads to no highlighting at all.

Changing the pattern to exclude ```{ :

 syn region rNameWSpace start="`\(``{\)\@!" end="`" contains=rSpaceFun

makes Rmd highlighting look like .R

with

syn match rOperator    "[|!<>^~`/:]"

And slightly better:

except with

syn match rOperator    "[|!<>^~/:]"

Though perhaps the ``` be treated as before (brown/gold). But I can't figure that out. The best I can do is:

with

syn match rOperator "```"

[jalvesaq]

It is preferable if the vim script to highlight R code is exactly the same in .R and .Rmd files. So, could you check the branch rmd_backtick, please? I deleted the "rmd" condition from syntax/r.vim and the chunk highlighting is still normal to me, as you can see in the image below:

[jalvesaq]

Sorry for taking so long to look at this carefully.