REPLConnect.R

R support for REPLConnect.nvim — connect Neovim to a running R session (designed for the arf console).

The repository has two parts:

replconnect/ — an R package (Rust core via extendr) that serves the session's variables, a grid data viewer, runtime completion, history and plots to Neovim over a Unix-domain socket, using the REPLConnect protocol. Requests are handled on R's main thread while R is idle at the prompt.
lua/replconnect/r.lua and plugin/replconnect-r.lua — a Neovim plugin that registers R as a language with the replconnect.nvim core.

Requirements

Neovim with replconnect.nvim (the core plugin) installed
R >= 4.2 on Linux or macOS
Cargo and rustc, only when building from source (not needed with r-universe binaries)
Optional: unigd (plot capture), tibble, data.table

Installation

Install the R package from r-universe, which provides prebuilt binaries (no Rust toolchain needed):

install.packages(
  "replconnect",
  repos = c("https://arnold-c.r-universe.dev", "https://cloud.r-project.org")
)

Or with pak:

# install.packages("pak")
pak::repo_add(arnold = "https://arnold-c.r-universe.dev")
pak::pkg_install("replconnect")

To build from source instead (requires Cargo and rustc):

pak::pak("arnold-c/REPLConnect.R/replconnect")

Add this repository to Neovim's runtimepath alongside replconnect.nvim, e.g. with lazy.nvim:

{
    "arnold-c/REPLConnect.R",
    dependencies = { "<owner>/REPLConnect.nvim" }
}

Setup

Add this to your ~/.Rprofile

if (interactive()) {
  replconnect::start()
  replconnect::capture_plots(TRUE)
}

Projects using renv

renv gives each project an isolated library, and R skips ~/.Rprofile when a project has its own .Rprofile (as renv projects do). To use replconnect in renv projects without adding it as a project dependency, install it into a separate personal library and tell renv about it.

From a session outside any renv project (e.g. R --vanilla), install into a dedicated library. Use a local checkout or r-universe:

lib <- path.expand("~/.R/dev-library")
dir.create(lib, recursive = TRUE, showWarnings = FALSE)
install.packages(
  "/path/to/REPLConnect.R/replconnect", # local source checkout
  lib = lib,
  repos = NULL,
  type = "source"
)
# or: install.packages("replconnect", lib = lib,
#       repos = "https://arnold-c.r-universe.dev")

Add to ~/.Renviron (use an absolute path):
```
RENV_CONFIG_USER_PROFILE=TRUE
RENV_CONFIG_EXTERNAL_LIBRARIES=/Users/<you>/.R/dev-library
```
user.profile makes renv source ~/.Rprofile on activation, and external.libraries adds the library to .libPaths() without recording it in renv.lock.

Use this in ~/.Rprofile, which works both inside and outside renv projects:

if (interactive()) {
  local({
    lib <- path.expand("~/.R/dev-library")
    if (requireNamespace("replconnect", lib.loc = c(.libPaths(), lib), quietly = TRUE)) {
      replconnect::start()
      replconnect::capture_plots(TRUE)
    }
  })
}

R API

Function	Purpose
`start()`	Start serving the session over a socket
`serving()`	Check whether the server is running
`shutdown()`	Stop the server
`capture_plots()`	Toggle forwarding of plots to Neovim
`record_history()`	Record console history for Neovim

Development

Tests live in replconnect/tests/ (testthat), spec/ and tests/ (Neovim), and the Rust core in replconnect/src/rust/core (cargo test).

License

See replconnect/LICENSE.