Amber Smalltalk

Amber includes an integrated development environment (IDE) with a class browser, Workspace, transcript, object inspector, and debugger. Amber is written in itself (is self-hosting), including the compiler, and compiles into JavaScript, mapping one-to-one with the JavaScript equivalent.[3] This one-to-one mapping with JavaScript differentiates Amber from other Smalltalk variants such as Pharo, Seaside, and Squeak.[1] Developing Amber project requires Node.js to run the tooling; the deployed project only needs browser to run. Amber doesn't run slowly on a bytecode virtual machine due to its convenient mapping to JavaScript, which makes compiled code run fast.

Amber was originally created by Nicolas Petton in 2011.[4] Amber was influenced by an earlier Smalltalk in browser project, named Clamato, created by Avi Bryant.[4][5] Amber and Clamato both use parsing expression grammar (PEG) libraries to parse Smalltalk source code. Amber uses the JavaScript based PEG.js library[6][7] written by David Majda. Clamato uses PetitParser, a Smalltalk-based library written by Lukas Renggli.[4] Clamato and Amber were both influenced by earlier work by Dan Ingalls in developing the Lively Kernel implementation of Morphic to run in web browsers via JavaScript.[4][8]

Starting with version 0.12.0, Amber modules compile to asynchronous module definition (AMD).[9] Starting with version 0.12.6, the development helper command-line interface (CLI) tool is extracted to dedicated module, which can be installed from npm as @ambers/cli; and setting up the project and its JavaScript ecosystem (npm, grunt) is greatly simplified using this CLI tool by issuing amber init and answering a few questions.[10] Since August 2018, project scaffolding of "amber init" is simplified, not using bower any more and only based on npm and whole project resides under npm organization @ambers. This makes setting Amber Smalltalk easier for people with little JavaScript experience.[11]

Up-to-date instructions should be at https://lolg.it/amber/amber.

To install Amber, Git must be installed first, if it is not already. The following commands will install Amber:[2]

# for macOS and Linux, needs the following two commands: 
npm config set prefix=~/npm
export PATH="$PATH:$HOME/npm/bin" # add to .bash_profile or .bashrc

npm install -g grunt-cli grunt-init @ambers/cli

To create a new project, write:

# Create the empty project dir
mkdir example-project
cd example-project

# Create and initialize a new Amber project
amber init

"amber init" step will lead to some questions about the project. For most of them, a default answer can be set. The next step is to start the server:

amber serve

After that, typing http://localhost:4000 in the browser will get to the application. Most browsers will block Helios IDE pop-ups by default, so browser settings may need changing to allow the Helios IDE popup to appear.

Npm software can be used to access a vast array of JavaScript libraries. A library can be integrated by following only four steps:[2]

1. Install the library using npm.
2. If 'local.amd.json' files doesn't exist for the npm package, create a 'libname.amd.json' file in the project root.
3. Run 'grunt devel' (or 'grunt deploy' if ready to deploy an application).
4. Add 'libname' to the application package's #imports: .

By running grunt deploy, the Amber project is packaged using RequireJS into just a few files, at the minimum just index.html and the.js. You can host those statically as any other static web page.

• Pharo
• Seaside (software)
• Squeak

• Official website
• Jtalk, the Smalltalk for Web developers Nicolas Petton, slides presented at ESUG 2011 (European Smalltalk User Group Conference). Edinburgh, Scotland, UK. (August, 2011)