Paul Krill
Editor at Large

Fable F# to JavaScript compiler improves usability, speed

news
Dec 7, 20202 mins

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

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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.

Paul Krill

Paul Krill is editor at large at InfoWorld. Paul has been covering computer technology as a news and feature reporter for more than 35 years, including 30 years at InfoWorld. He has specialized in coverage of software development tools and technologies since the 1990s, and he continues to lead InfoWorld’s news coverage of software development platforms including Java and .NET and programming languages including JavaScript, TypeScript, PHP, Python, Ruby, Rust, and Go. Long trusted as a reporter who prioritizes accuracy, integrity, and the best interests of readers, Paul is sought out by technology companies and industry organizations who want to reach InfoWorld’s audience of software developers and other information technology professionals. Paul has won a “Best Technology News Coverage” award from IDG.

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