Dart backend for Ceylon

Update (6/5/2017)

Developer preview release 4 (DP4) of the Dart backend for Ceylon is now available

This release is compatable with Ceylon 1.3.2 and contains several bug fixes and enhancements over DP3.

Update (9/27/2016)

Developer preview release 3 (DP3) of the Dart backend for Ceylon is now available

This release is compatable with Ceylon 1.3.0 and contains several bug fixes and enhancements over DP2.

Update (7/13/2016)

Developer preview release 2 (DP2) of the Dart backend for Ceylon is now available

This release includes:

• Complete support for the Ceylon 1.2.2 language, except reified generics and the metamodel.
• A familiar CLI for compiling and running Ceylon programs (ceylon compile-dart and ceylon run-dart).
• A powerful application assembly tool (ceylon assemble-dart) that can produce distributable Dart VM applications, single file Dart VM applications, and single file JavaScript applications.
• Eleven Ceylon SDK modules
• Initial support for Dart interop, including async/await, the ceylon.interop.dart module, and the ability to import and use 11 native Dart modules such as dart.core, dart.collection, and dart.html.

Installing the Dart backend for Ceylon

The commandline interface for the Dart backend is available on [Ceylon Herd] (https://modules.ceylon-lang.org/modules/com.vasileff.ceylon.dart.cli), and can be easily installed on any OS X or Linux system.

Step 1: Install Ceylon

To install Ceylon, see http://ceylon-lang.org/download/. Ceylon 1.3.2 is required.

Step 2: Install Dart

Homebrew users on OS X can install Dart with:

$ brew tap dart-lang/dart
$ brew install dart

For Linux users, Dart is available as either a Debian package or zip download from https://www.dartlang.org/downloads/.

Step 3: Install the Ceylon/Dart CLI Plugin

The commandline interface can be installed with:

$ ceylon plugin install --force com.vasileff.ceylon.dart.cli/1.3.2-DP4

Upon using ceylon compile-dart or ceylon run-dart for the first time, you will be prompted to complete the installation by running:

$ ceylon install-dart --out +USER

This will install the Ceylon language module, several Ceylon SDK modules, and several Dart interop modules into your local Ceylon module repository, which, for default Ceylon installations, is located at ~/.ceylon/repo.

And that's it!

Please note that upon running the commandline tools the first time, additional dependencies may be downloaded. No feedback is provided that this is happening, and canceling early may result in a corrupted download. So please be patient!

Using the Commandline Interface

Commandline tools for compiling and running Ceylon programs on the Dart VM mirror the tools used for the JVM and JavaScript backends:

• ceylon compile-dart to compile Ceylon modules to Dart
• ceylon run-dart to run compiled Ceylon modules on the Dart VM

A third tool, ceylon assemble-dart, package a Ceylon module as a standalone executable for the Dart VM.

Ok, it's installed, what do I do now?

There are three main types of applications that can be written today:

• command line applications,
• web client (JavaScript) applications using dart.html, and
• server side applications using dart.io

Support for pure-Ceylon CLI applications is quite advanced and supports nearly all valid Ceylon 1.3.2 programs. Modules can be compiled, run, and even imported using standard Ceylon tools and conventions. See the "Hello, World" walkthrough below to get started.

Check back soon for more on building server and web applications. For now, you might want to check out ColorTrompon, which is a Ceylon syntax highligher, written in Ceylon, compiled with ceylon compile-dart colortrompon, and packaged as a JavaScript application with ceylon assemble-dart mode=js colortrompon.

"Hello, World" Walkthrough

If you're new to Ceylon, you can perform the following steps to compile and run your first program.

First, use the ceylon new command to create an initial project structure:

$ ceylon new hello-world
Enter project folder name [helloworld]: 
Enter module name [com.example.helloworld]: 
Enter module version [1.0.0]: 
Would you like to generate Eclipse project files? (y/n) [y]: 
Enter Eclipse project name [com.example.helloworld]: 
Would you like to generate an ant build.xml? (y/n) [y]: 

$ cd helloworld/

In the newly created helloworld directory, you will find source/com/example/helloworld containing the main run.ceylon source code along with module.ceylon and package.ceylon module and package descriptors.

Now, from within the helloworld directory, the program can be compiled with:

$ ceylon compile-dart
Note: Created module com.example.helloworld/1.0.0

which creates a modules directory, and places the Dart output in the file modules/com/.../com.example.helloworld-1.0.0.dart

Run the program with the ceylon run command, specifying the module name and arguments:

$ ceylon run-dart com.example.helloworld 'Ceylon on Dart'
Hello, Ceylon on Dart!

Or, if you like, create a single-file application:

$ ceylon assemble-dart --out helloworld com.example.helloworld
Created executable Dart script helloworld

and run as you would any other executable:

$ ./helloworld 'Ceylon on Dart, without the Java!!'
Hello, Ceylon on Dart, without the Java!!!

Of course, you'll want to write much more sophisticated programs that take advantage of Ceylon's advanced but easy to use type system and features. To learn more, see the Ceylon language tour.

You can also try Ceylon online, but be sure to copy the examples locally, and try them out on the Dart backend!

About the ceylon new Command

Note that the ceylon new command is not Dart specific; it is a standard command available with Ceylon 1.3.2. For help using the command, use ceylon help new.

You may notice options to create Eclipse and Ant configuration files. While Eclipse and Ant support is not currently available for the Dart backend, these options may still be useful, as you might use Eclipse to develop a module using the Java or JavaScript backend, and then drop to the CLI to compile for Dart.

Also note that the first argument to ceylon new must be the name of a template. Of the three templates available as part of Ceylon 1.3.2, hello-world and simple can be used for Dart projects. For example, to get started with a blank project, you might use:

ceylon new simple --module-name=com.mydomain.myproject myprojectDir

Ceylon/Dart DP2 Release Details

SDK Modules Included in DP2

Several Ceylon SDK modules ship with DP2:

• ceylon.buffer allows you to convert between text and binary forms of data
• ceylon.collection provides general-purpose mutable lists, sets, and maps
• ceylon.html allows you to write HTML templates for both server and client using only Ceylon
• ceylon.interop.dart types and utilities to work with native Dart code and libraries,
• ceylon.json contains everything required to parse and serialise JSON data
• ceylon.numeric provides common math functions for floats and integers
• ceylon.promise support for promises loosely based upon the A+ specification
• ceylon.random provides a pseudorandom number generator and extendable API
• ceylon.test simple framework to write repeatable tests
• ceylon.time is a date and time library library that is loosely inspired by the JodaTime/JSR-310 library
• ceylon.whole provides arbitrary-precision integer numeric type

Dart Interop Modules Included in DP2

Several Dart modules can be imported by DP2 programs:

• dart.async
• dart.collection
• dart.convert
• dart.core
• dart.developer
• dart.html
• dart.io
• dart.isolate
• dart.math
• dart.mirrors
• dart.typed_data

License

The content of this repository is released under the ASL v2.0 as provided in the LICENSE file that accompanied this code.

By submitting a "pull request" or otherwise contributing to this repository, you agree to license your contribution under the license mentioned above.