Trajectory for evaluating adding Automatic Differentiation to Swift

[dan-zheng]

Hi Frederic,

Thanks for raising your concern! Our differentiable programming manifesto (written in a Swift Evolution format) may help give you some context on our vision. I'd recommend the following sections in particular:

• "Approaches to automatic differentiation": we mention existing approaches to automatic differentiation, including library-based approaches, source code transformation tools, and language integration.
• "Why bake differentiation into Swift?": we make the case that first-class language support for differentiation will enable convenient, extensible, and performant differentiable programming in Swift.

The forum thread below has more discussions, if you're curious:

Differentiable Programming Mega-Proposal

Hi Swift community, We have completed a comprehensive proposal for the differentiable programming feature we’ve been incubating over the last 1.5 years. We’ve gone over many iterations on the feature design, and have partially completed the implementation. Now we are ready to start a discussion on Swift Evolution, specifically on upstreaming and standardizing the feature. Since this proposal is overly long (~60 pages), we hope to start by merging it into the docs/ directory in apple/swift via a…