[154] Issue #154 - February 27, 2020

[BasThomas]

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[BasThomas]

https://twitter.com/tkremenek/status/1227980480026312704

A great writeup from @slava_pestov on Swift's library evolution capabilities: https://swift.org/blog/library-evolution/

[MaxDesiatov]

swiftlang/swift#29530 was merged to Swift master that upstreams almost a quarter of the huge patch swiftlang/swift#24684 from the SwiftWasm team, which brings us closer to enabling WebAssembly/WASI target in the compiler and running Swift code in browsers.

[fassko]

Lifting the 1 variadic param per function restriction

I've got a quick pitch here on lifting the restriction that each function can only have a single variadic param, inspired by a conversation started by @anandabits on twitter. It turns out this restriction is now easy to lift, so without further ado:

Functions with Multiple Variadic Parameters
Implementation: swiftlang/swift#29735

Introduction
Currently, variadic function parameters in Swift have two main restrictions:

• Only one variadic parameter is allowed per function
• If present, the parameter which follows a variadic parameter must be labeled
  This proposal seeks to remove the first restriction while leaving the second in place, allowing a function to have multiple variadic parameters so long as every parameter which follows a variadic one has a label.

https://forums.swift.org/t/lifting-the-1-variadic-param-per-function-restriction/33787

[BasThomas]

swiftlang/swift#24303

[wlisac]

I released a new logging backend for SwiftLog that could make a fun / lightweight addition to this week's newsletter 😊

https://twitter.com/wlisac/status/1229108200131031040

[fassko]

[Manifesto] Interoperability between Swift and C++

Interoperability between Swift and C++ has been previously discussed on the forums ([1], [2], [3]). The Swift for Tensorflow project has already started to build it out under the hidden -enable-cxx-interop flag. I have been trying to understand what interop will look like across all C++ features. I have summarized possible design options in a manifesto: Interoperability between Swift and C++.

It is not a fully finalized design: many sections list multiple alternative options that we should discuss and evaluate their pros and cons. Some sections are missing, notably, calling Swift from C++. Nevertheless, this manifesto covers enough ground to show what Swift/C++ interop could look like, what will work well, and where the rough edges are.

https://forums.swift.org/t/manifesto-interoperability-between-swift-and-c/33874

And Survey:

https://forums.swift.org/t/swift-c-user-survey-how-would-you-use-c-interoperability/33875

[fassko]

CVE-2019-15605: SwiftNIO: HTTP request smuggling using malformed Transfer-Encoding header

SwiftNIO before 2.13.1 (and SwiftNIO 1 before 1.14.2) are vulnerable to CVE-2019-15605: HTTP request smuggling using malformed Transfer-Encoding header.

Please make sure you immediately upgrade to SwiftNIO >= 2.13.1 (or >= 1.14.2 for SwiftNIO 1)

https://forums.swift.org/t/cve-2019-15605-swiftnio-http-request-smuggling-using-malformed-transfer-encoding-header/33876

[MaxDesiatov]

@kateinoigakukun has posted here a quite detailed update on the progress of the WebAssembly compiler target:

https://forums.swift.org/t/wasm-support/16087/14

[fassko]

Support building Rust targets in SPM?

Swift Package Manager already supports building Swift, C, C++ and assembly code.

I've just come up with this crazy idea: what if we allow SPM to build Rust targets?

https://forums.swift.org/t/support-building-rust-targets-in-spm/33898

[BasThomas]

https://twitter.com/slava_pestov/status/1229863852411629568

This is incredible. The diagnostics engine rewrite is in a sense now “done”, and the expression checker folks are now ready to rip out the old implementation completely: swiftlang/swift#29906

[BasThomas]

https://twitter.com/tkremenek/status/1229882956971294720

Swift now has Swift Package Manager packages to try out forthcoming Standard Library changes! https://swift.org/blog/preview-package/