How to create new tag for customising the existing section Description?

[ramiromagno]

Here is an example of what I am trying to achieve.

Here is a snippet of an roxygen comment block:

#' Rf_mkCharLenCE
#'
#' @description
#'
#' \Sexpr[results=rd, stage=render]{c3po:::badge('fnp')} \Sexpr[results=rd, stage=render]{c3po:::badge('c2r')} \Sexpr[results=rd, stage=render]{c3po:::badge('prot')}
#'
#' TODO
#'
#' @section Declaration:
#' ```
#' SEXP Rf_mkCharLenCE(const char *name, int len, cetype_t enc);
#' ```

Now, you see those three \Sexpr commands? They are analogous to those used, e.g., in rlang:

https://github.com/r-lib/rlang/blob/a90b04b9d6a17f1aabadaed357784efc22116d2a/R/eval-tidy.R#L1-L6

I use them to generate nice looking svg badges in my documentation.

My question is: would it be possible to generate a new tag, say, @badge that accepts keywords and acts on them by generating the corresponding code described above? I mean something like:

#' @badge fnp c2r prot

in context:

#' Rf_mkCharLenCE
#'
#' @description
#'
#' @badge fnp c2r prot
#'
#' TODO
#'
#' @section Declaration:
#' ```
#' SEXP Rf_mkCharLenCE(const char *name, int len, cetype_t enc);
#' ```

From what I have read from the docs, creating a new tag creates a new section, so it would not apply to my case here because I need to edit an existing section, i.e., Description. So it seems to me that creating a new roclet is the way to go but I am not sure still if I can use that approach to change an existing section such as Description... I am sorry if I sound confusing, it could be because I am confused :) See also my other question about what is a roclet: #1086.

[hadley]

You could use inline R code.