Fable F# to JavaScript compiler improves usability, speed

The Fable 3 ‘Nagareyama’ release promises to be easier to use and to cut compilation speed in half.

Fable F# to JavaScript compiler improves usability, speed
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Fable 3, the latest release of the Fable compiler for writing JavaScript applications with Microsoft’s F# functional language, is now available, offering simpler usage, more readable code, and improved compilation speed.

Fable 3, aka Nagareyama, removes inter-process communication with JavaScript, to greatly simplify Fable usage and development. Compilation speed also has been improved, with Fable 3 developers anticipating compiling processes to be reduced by half.

Other improvements cited for Fable 3 Nagareyama, which was released December 4, include:

  • The compiler is no longer tightly coupled with a specific bundler like Webpack, enabling it to be used with any bundling tool developers want to use.
  • Plug-ins can be accepted from library authors.
  • Fable is now a .NET tool.
  • No breaking changes. Fable 2 projects should compile as is.
  • Generated code is more readable and easier to debug.

The builders of the Fable tool note that the upgrade is probably not bug-free. But release candidates have been tested in many projects and all outstanding issues have been fixed. Instructions on using Fable can be found at fable.io.

Powered by the Babel compiler, Fable produces readable JavaScript code that is compatible with ES2015 and tools such as Webpack. Fable is intended to make F# a first-class citizen of the JavaScript ecosystem.

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