https://github.com/extendr/rextendr/issues/291

rust_source.R

library(glue)
library(stringr)
require(rlang)
require(rextendr)
# drop-in replacement for rextendr::rust_source
# use a build directory in the current working directory
# if the source file is lib.rs the build is in lib_build
# code= needed for https://github.com/extendr/rextendr/issues/234
rust_source <- function(file, code= paste0(readLines(file), collapse="\n"), features="ndarray", ...) {
        # https://github.com/extendr/rextendr/issues/291
        rlang::env_bind(rextendr:::the, build_dir = {
              b <- file.path(getwd(), glue("{str_remove(file, '.rs')}_build"))
              if (!dir.exists(b)) {
                      dir.create(b)
                      dir.create(file.path(b, "src"))
                      dir.create(file.path(b, "R"))
                      dir.create(file.path(b, ".cargo"))
              }
              b
        })
        rextendr::rust_source(code = code, features=features,
                env = parent.frame(), ... )
}