A Possible Vision for Macros in Swift

CommunityNews · 18 October 2022 13:18

A possible vision for macros in Swift.
A possible vision for macros in Swift. GitHub Gist: instantly share code, notes, and snippets.

Read in full here:

gist.github.com

https://gist.github.com/DougGregor/4f3ba5f4eadac474ae62eae836328b71

macros.md

# A Possible Vision for Macros in Swift

As Swift evolves, it gains new language features and capabilities. There are different categories of features: some fill in gaps, taking existing syntax that is not permitted and giving it a semantics that fit well with the existing language, with features like conditional conformance or allowing existential values for protocols with `Self` or associated type requirements. Others introduce new capabilities or paradigms to the language, such as the addition of concurrency or comprehensive reflection. 

There is another large category of language features that provide syntactic sugar to eliminate common boilerplate, taking something that can be written out in long-form and making it more concise. Such features don't technically add any expressive power to the language, because you can always write the long-form version, but their effect can be transformational if it enables use cases that would otherwise have been unwieldy. The synthesis of `Codable` conformances, for example, is sheer boilerplate reduction, but it makes `Codable` support ubiquitous throughout the Swift ecosystem. Property wrappers allow one to factor out logic for property access, and have enabled a breadth of powerful libraries. New language features in this category are hard to evaluate, because there is a fundamental question of whether the feature is "worth it": does the set of use cases made better by this feature outweigh the cost of making the language larger and more complicated?



## Democratizing syntactic sugar with macros

This file has been truncated. show original

This thread was posted by one of our members via one of our news source trackers.