sdk/pkg/dev_compiler/USAGE.md

Usage

The Dart Dev Compiler (DDC) is an experimental development compiler from Dart to EcmaScript 6. It is still incomplete, under heavy development, and not yet ready for production use.

With those caveats, we welcome feedback for those experimenting.

The easiest way to compile and run DDC generated code for now is via NodeJS. The following instructions are in a state of flux -- please expect them to change. If you find issues, please let us know.

1. Follow the Getting the Source steps, and set the environment variable DDC_PATH to the pkg/dev_compiler subdirectory within wherever you check that out.

2. Install nodejs v6.0 or later and add it to your path. It can be installed from:

   https://nodejs.org/

   Note, v6 or later is required for harmony / ES6 support.

3. Define a node path (you can add other directories if you want to separate things out):

   export NODE_PATH=$DDC_PATH/lib/js/common:.
   

4. Compile a test file with a main entry point:

   dart $DDC_PATH/bin/dartdevc.dart --modules node -o hello.js hello.dart
   

   Note, the hello.js built here is not fully linked. It loads the SDK via a require call.

5. Run it via your node built in step 1:

   node -e 'require("hello").hello.main()'
   

6. Compile multiple libraries using summaries. E.g., write a world.dart that imports hello.dart with it's own main. Step 5 above generated a summary (hello.sum) for hello.dart. Build world:

   dart $DDC_PATH/bin/dartdevc.dart --modules node -s hello.sum -o world.js world.dart
   

   Run world just like hello above:

   node -e 'require("world").world.main()'
   

7. Node modules do not run directly on the browser or v8. You can use a tool like browserify to build a linked javascript file that can:

   Install:

   sudo npm install -g browserify
   

   and run, e.g.,:

   echo 'require("world").world.main()' | browserify -d - > world.dart.js
   

   The produced world.dart.js fully links all dependencies (dart_sdk, hello, and world) and executes world.main. It can be loaded via script tag and run in Chrome (stable or later).

Feedback

Please file issues in our GitHub issue tracker.