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Rikito Taniguchi (@tanishiking)
(Weekend OSS contributor to Scala tooling)
Tooling for Scala 3
Reactive System Meetup#7
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Scala 3 has
landed 🎉
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Requirements for transition to Scala 3
Requirements IMO
• Stabilizing the compiler
• More learning resources
• Libraries support for Scala 3
• Tooling support for Scala 3 👈 today’s topic
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Tooling for Scala 3
scalameta based tools
• scalafmt
• scala
fi
x
• metals
TL;DR Basic Scala 3 supports are already done.
Ready to use!
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Scalafmt & Scala 3
scalafmt v3 supports Scala 3
Specify runner.dialect = scala3 .scalafmt.conf
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Scalafix & Scala 3
Scala
fi
x v0.9.28 introduces experimental Scala 3 support !
https://github.com/liancheng/scala
fi
x-organize-imports#scala-3
liancheng/scala
fi
x-organize-imports
works with Scala 3
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Write your own rule for Scala 3
sbt new scalacenter/scala
fi
x.g
8
↑ generates a rule template that runs both on Scala 2 and
Scala
3
You can write both SyntacticRule and SemanticRule
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Metals & Scala 3
Metals works with Scala 3 !
Code Completion
Code Navigation / Hover
Show inferred type (will be available with Scala 3.1.0)
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Metals & Scala 3 - Missing features
Some advanced features are still missing in Scala 3 😢
Exhaustive case completion Implement abstract members
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Today’s takeaway
• Many tools already have basic supports for Scala 3 !
• Some features are missing… need more e
ff
ort 💪
• Please try it out, and give us feedback.
HAPPY CODING WITH SCALA 3 !!