An analysis of Swift Evolution proposals
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proposal-page-generator.xcodeproj auto-update proposals Jan 8, 2017
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.gitignore add initial page generator Sep 11, 2016
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main.swift update markdown Sep 11, 2016 fix the script bug (#7) Dec 5, 2016


An analysis of Swift Evolution proposals


All of the swift-evolution proposals are publicly available on GitHub, however they are just markdown files — plain text. There's no way to query or filter the proposals. For example, you can't search for "all proposals written by Chris Lattner" or "all rejected proposals" or "all proposals that mention Objective-C".

This project contains tools to analyze, query, and filter the Swift Evolution proposals based on any criteria you like.

This project accompanies my talk from FrenchKit.


  • macOS 10.11+
  • Xcode 8
  • Swift 3.0


This repo contains a number of different components:

  • The swift-evolution repo is a git submodule. This is how proposals are synced to stay updated.
  • main.swift is a swift script that generates playground pages for all of the proposals. You can open proposal-page-generator.xcodeproj to modify the script.
  • swift-proposal-analyzer.playground is the main playground that contains:
    • All of the proposals as playground pages
    • All of the proposals as raw Resources/
    • The analyzer code
  • is a bash script that does the following:
    1. Updates the swift-evolution submodule
    2. Copies the proposals from the submodule directory, into the playground Resources/ directory
    3. Runs main.swift to generate the playground pages

Cloning this repo

$ git clone
$ cd swift-proposal-analyzer/
$ git submodule init
$ git submodule update --remote
$ ./


Open and run swift-proposal-analyzer.playground.

After parsing completes, you'll have an array of Proposal types:

public final class Proposal {
    public let title: String
    public let seNumber: String

    public let authors: [Author]
    public let status: Status

    public let fileName: String
    public let fileContents: String
    public let wordCount: Int

Most proposal metadata is available, as well as the raw file contents. You can now perform different queries or apply filters to the proposal data.


// Find proposals implemented in Swift 3.0
let implementedInSwift3 = analyzer.proposalsWith(status: .implemented(.v3_0))
// Find proposals authored or co-authored by Chris Lattner
let proposalsByLattner = analyzer.proposals.filter { p -> Bool in
    p.writtenBy("Chris Lattner")
// Find total mentions of "Objective-C" across all proposals
let count = analyzer.occurrences(of: "Objective-C")


Some of the code here is pretty "quicky and dirty", but it works! So ¯\_(ツ)_/¯ 😆 If there's a better way to do something, please submit a pull request!

This is a small dataset, so any conclusions should be taken with a grain of salt. 😄


Created and maintained by @jesse_squires.


Released under an MIT License. See LICENSE for details.

Copyright © 2016-present Jesse Squires.