This is a
playground to test code. It runs a full
Node.js environment and already has all of
npm’s 400,000 packages pre-installed, including
fable-compiler with all
npm packages installed. Try it out:
This service is provided by RunKit and is not affiliated with npm, Inc or the package authors.
Fable is distributed through npm! You can install and run it just by typing:
npm install -g fable-compiler fable path/to/your/project.fsproj
Note the package name is
fable-compilerwhile the command is just
If you are having problems to use Fable under Windows, try the following:
fsc.exeis added to the path.
Just by using Fable you're already contributing! You can help a lot the community by sharing examples and experiences in your personal blog or by sending a PR to Fable's website (see this for more info).
Send bug reports (ideally with minimal code to reproduce the problem) and feature requests
to the GitHub repository. Issues with the label
discussion will be also added to ask the opinion of the community
on different topics like the logo, roadmap, etc. For more immediate comments you can use the Gitter chat.
A plugin system is also available to allow you extend Fable according to you needs.
Options are erased in compiled code. This has several benefits like removing overhead
and interacting with native JS functions in a safer way (
null will be
However, it will lead to unexpected results if you do weird things like wrapping
For practical purposes, Fable considers
unit to be the same thing.
To know more, read Compatibility.
Of course, this project wouldn't have been possible without the fantastic work of the F# compiler and Babel teams. I hope they feel proud seeing how their work has met in a very unexpected way, giving developers even more possibilities to build great apps.
The awesome F# community has played a big role in making this possible. I've met incredible people and it's impossible to list all the names without forgetting anyone, but I'd like to give a particular mention to Zach Bray for his work on FunScript, Don Syme (the fact that the designer of the language himself shows interest in your work, no matter how humble it is, is really a big push!) and Krzysztof Cieślak (I always have to look up the name to spell it correctly) because he's shown that F# is a perfect fit for a big project targeting JS.
And finally I'd like to thank my partner (is it too old-fashioned to say wife?) for bearing with me everyday.