Typed throws のプロポーザルが出ましたね． https://github.com/DougGregor/swift-evolution/blob/typed-throws/proposals/nnnn-typed-throws.md https://github.com/apple/swift-evolution/pull/2184

swift-evolution/proposals/nnnn-typed-throws.md at typed-throws · Do...

This maintains proposals for changes and user-visible enhancements to the Swift Programming Language. - DougGregor/swift-evolution

Typed throws proposal by DougGregor · Pull Request #2184 · apple/sw...

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