Create a webR REPL sharelink from R code

Turns a single R script into a URL that runs it in the webR REPL.

Usage

webr_repl_link(
  input = NULL,
  filename = "script.R",
  path = NULL,
  autorun = FALSE,
  panels = NULL,
  version = "latest",
  base_url = NULL
)

Arguments

input

Code input. Can be:

R expression (no quotes needed): webr_repl_link({ plot(1:10) })
Character string: R code to execute
File path: Path to R file to read
NULL: Read from clipboard (requires clipr package)

filename

Name for the file (default: "script.R")

path

Full path where the file will be placed in webR. If NULL (default), the file is placed at "/home/web_user/{filename}".

autorun

Logical. Whether to auto-execute the code when link is opened (default: FALSE). Only R files (.R) can be auto-executed.

panels

Character vector or string specifying which webR interface panels to show. The panels are "plot", "files", "terminal", and "editor". Can be c("plot", "files") or "plot-files". If NULL (default), shows all panels.

version

webR version to use ("latest" or specific version >= "v0.5.4")

base_url

webR application URL. If NULL, uses global option or builds from version

Value

A webr_link object, which is a list with these entries.

url, the sharelink itself, as a single string.
filename, the name the script is given inside webR.
path, where that file is placed inside webR.
mode, the panels the link asks for, or NULL for all of them.
version, the webR version the link points at.
autorun, TRUE when the code runs as soon as the link opens.

Use as.character() on the object to get the URL on its own.

Details

The code travels inside the URL, in the fragment after the #, which browsers keep local and never send to a server. Opening the link boots webR in the reader's own tab, so nothing is installed and nothing runs on your side.

input is deliberately permissive. It takes an expression in braces, a string, a path to a file, or the clipboard when nothing is passed at all. One script goes in one link. For several files, see webr_repl_project().

Comments in expression input

Expression input recovers your code from the source R kept when it read the expression. R only keeps that source when keep.source is enabled, so comments survive in an interactive session but are dropped when the calling code is read without it. That is what happens inside a knitted 'Quarto' or 'R Markdown' document, because 'knitr' evaluates chunks through evaluate::evaluate(), which throws the source away. No keep.source setting recovers them there.

If you need comments preserved, pass the code as a string or a file path, or write it as a chunk in the document. See livelink-knitr and vignette("links-in-documents", package = "livelink").

Examples

# Expression input (no quotes needed!)
webr_repl_link({
  plot(1:10)
  summary(mtcars)
})
#> 
#> ── webR Link ──
#> 
#> <https://webr.r-wasm.org/latest/#code=eJyb2LwkLzE3dUVxclFmQYle0JKCxJKM7foZ%2Bbmp%2BuWpSfGlxalF%2BnDJktSKkl0FOfklGoZWhgaaXMWlubmJRZUauSXJiUXFmgDuJR64&mz>
#> 
#> File: script.R → /home/web_user/script.R
#> Version: "latest"
#> Autorun: FALSE

# Traditional string input
webr_repl_link("plot(1:10)")
#> 
#> ── webR Link ──
#> 
#> <https://webr.r-wasm.org/latest/#code=eJyb2LwkLzE3dUVxclFmQYle0JKCxJKM7foZ%2Bbmp%2BuWpSfGlxalF%2BnDJktSKklUFOfklGoZWhgaaAC8DGLU%3D&mz>
#> 
#> File: script.R → /home/web_user/script.R
#> Version: "latest"
#> Autorun: FALSE

# Choose which panels the REPL shows
webr_repl_link({ hist(rnorm(100)) }, panels = c("plot", "editor"))
#> 
#> ── webR Link ──
#> 
#> <https://webr.r-wasm.org/latest/?mode='plot-editor'#code=eJyb2LwkLzE3dUVxclFmQYle0JKCxJKM7foZ%2Bbmp%2BuWpSfGlxalF%2BnDJktSKkg0ZmcUlGkV5%2BUW5GoYGBpqaANHPGvg%3D&mz>
#> 
#> File: script.R → /home/web_user/script.R
#> Interface: "Plot" and "Editor"
#> Version: "latest"
#> Autorun: FALSE

# Run the code as soon as the link opens
webr_repl_link("plot(1:10)", autorun = TRUE)
#> 
#> ── webR Link ──
#> 
#> <https://webr.r-wasm.org/latest/#code=eJyb2LIkLzE3dUVxclFmQYle0JKCxJKM7foZ%2Bbmp%2BuWpSfGlxalF%2BnDJktSKklUFOfklGoZWhgaayxNLS%2FKLSvMOAwAjdx0u&mza>
#> 
#> File: script.R → /home/web_user/script.R
#> Version: "latest"
#> Autorun: TRUE

# File path input
script <- tempfile(fileext = ".R")
writeLines("plot(1:10)", script)
webr_repl_link(script)
#> 
#> ── webR Link ──
#> 
#> <https://webr.r-wasm.org/latest/#code=eJyb2LwkLzE3dUVxclFmQYle0JKCxJKM7foZ%2Bbmp%2BuWpSfGlxalF%2BnDJktSKklUFOfklGoZWhgaaAC8DGLU%3D&mz>
#> 
#> File: script.R → /home/web_user/script.R
#> Version: "latest"
#> Autorun: FALSE

# Read the code from the clipboard
if (interactive()) {
  webr_repl_link()
}