White space breaks chunk regexes?

[jamiefolson]

Not sure if this is desired, but if there's any whitespace in front of a chunk, it's not detected, e.g. " <<>>=...@" instead of "<<>>=...2"

[yihui]

this is the default syntax inherited from Sweave, and I guess the main consideration is to make it as unique as possible because it serves as the marker of code chunks

you can customize the syntax like this (see http://yihui.name/knitr/patterns):

library(knitr)
pat_rnw()  # default syntax
knit_patterns$set(chunk.begin = "^\\s*<<(.*)>>=", chunk.end = "^\\s*@\\s*%*")

\\s* means white spaces.

Is there a special reason that you need to add white spaces before <<>>=?

[vspinu]

Hi Yihui,

I have started looking into knitr to find ways to integrate into ESS. So far I am really impresed. Thanks for your work. Be sure that we will have a full blown support for knitr in the next version (September I guess).

This issue is crucial for proper indentation of code chunks inside Latex docs when chunks are not at top level.

For example you might want to have a chunk inside itemize environment and to indent the code according to latex rules. Would be good to allow spaces in front of << and @ by default.

[yihui]

Actually I believe this is a fair request now, because sometimes I also want the code blocks to be indented, especially in markdown. White spaces do not really have any influence on LaTeX output, but they do have a meaning for markdown. So I think I will change the syntax to allow white spaces before << and @.

I'm thrilled to know knitr is going to ESS. Thanks!

[yihui]

hi @jamiefolson and @Vitoshka,

now leading spaces are allowed in chunk headers, so you are free to indent the chunks; see https://github.com/yihui/knitr/blob/master/NEWS.md#major-changes

[github-actions]

This old thread has been automatically locked. If you think you have found something related to this, please open a new issue by following the issue guide (https://yihui.org/issue/), and link to this old issue if necessary.