nochiel
commented
1 year ago Summary
What is required by BlockckainCommons' Swift projects.
- BlockckainCommons/BCSwiftDCBOR expects Swift 5.7.
- envelope-cli-swift expects Swift 5.7.
Can we use any automatic Swift-Kotlin translation tools?
- angelolloqui/SwiftKotlin
- I don't recommend using SwiftKotlin.
- As of 2022 it is not maintained.
- The last commit was https://github.com/angelolloqui/SwiftKotlin/commit/a2f50476ce78d407cddee9a52ee1b59e2957730d 2020/12/08.
- Swift 5.7 was released on 2022/09/12
- vinivendra/Gryphon
- I don't recommend using Gryphon.
- As of 2022/12/19, Gryphon is no longer maintained.
- The latest version https://github.com/vinivendra/Gryphon/releases/tag/v0.19 supports Swift 5.2 to 5.6.
- Translation of Swift packages requires XCode because Package.swift isn't supported.
- With modification Gryphon it might be possible to use Gryphon to translate using a
Package.swiftfor Swift 5.7 but it's unclear how much work this would be. Additionally, BlockchainCommons would have to commit to maintaining its own fork of the Gryphon.
Challenges in translating Blockchain Commons CLI tools from Swift to Kotlin
- We need to translate Swift dependencies.
- C dependencies: These can be used from Kotlin's cinterop.
- C++ dependencies: Support for C++ is undocumented. We need to test relevant BlockchainCommons libraries in this regard. I believe they should work from Kotlin because most header files for these libraries are pure C.
Recommendations
- Manual (that is, by hand) translation of the BlockchainCommons' Swift libraries and CLI tools is preferable. Kotlin's semantics and idioms are quite similar to Swift's. In particular, Kotlin's type system compares favourably with Swift's.
- Translation by hand has been done to Rust for some libraries and tools. This should simply the process of doing a translation to Kotlin as there is often a Rust translation to compare with.
thunderbiscuit
NB: This should be done in time for the meeting on 2023/03/01.