Nbb

Not babashka. Node.js babashka!?

Previously known as TBD and Nodashka.

Status

Experimental.

Usage

Install nbb from NPM:

$ npm install -g nbb

and perhaps some other NPM libraries to use in the script. E.g.:

$ npm install csv-parse
$ npm install shelljs

Create a script which uses the NPM libraries:

(ns script
  (:require ["csv-parse/lib/sync" :as csv-parse]
            ["fs" :as fs]
            ["shelljs" :as sh]))

(println (count (str (fs/readFileSync "script.cljs"))))

(prn (sh/ls "."))

(prn (csv-parse "foo,bar"))

Call the script:

$ nbb script.cljs
264
#js ["CHANGELOG.md" "README.md" "bb.edn" "deps.edn" "main.js" "node_modules" "out" "package-lock.json" "package.json" "shadow-cljs.edn" "src" "test.cljs"]
#js [#js ["foo" "bar"]]

Reagent

Nbb includes reagent.core which will be lazily loaded when required. You can use this together with ink to create a TUI application:

$ npm install ink

ink-demo.cljs:

(ns ink-demo
  (:require ["ink" :refer [render Text]]
            [reagent.core :as r]))

(defonce state (r/atom 0))

(doseq [n (range 1 11)]
  (js/setTimeout #(swap! state inc) (* n 500)))

(defn hello []
  [:> Text {:color "green"} "Hello, world! " @state])

(render (r/as-element [hello]))

Startup time

The baseline startup time for a script is about 200ms seconds on my laptop. When invoked via npx this adds another 300ms or so, so for faster startup, either use a globally installed nbb or use $(npm bin)/nbb script.cljs to bypass npx.

Build

Prequisites:

• babashka >= 0.4.0
• Clojure CLI >= 1.10.3.933
• Node.js 16.5.0 (lower version may work, but this is the one I used to build)

To build:

• Clone and cd into this repo
• bb release

License

Copyright © 2021 Michiel Borkent

Distributed under the EPL License. See LICENSE.