CodaFi

/// Playground - noun: a place where people can play
/// I am the very model of a modern Judgement General

//: # Algorithm W

//: In this playground we develop a complete implementation of the classic
//: algorithm W for Hindley-Milner polymorphic type inference in Swift.

//: ## Introduction

CodaFi

final class Nat<F> : FunctorOf<F> {	
	let pred : Optional<F>
	
	override init() {
		self.pred = nil
	}
	
	init(pred : F) {
		self.pred = pred
	}

CodaFi

Motivation

Swift’s type system supports a number of different ways of taking a function or type and abstracting it. Usually, this is done by adding a generic parameter and an associated set of constraints. Similarly, a function that takes a particular type of argument can be abstracted to any number of those arguments by making it variadic with triple-dot (...) syntax. Today, both of these features are permitted separately: you can define a generic function that takes a variable number of arguments, such as

func debugPrint<T>(_ items: T...) 
  where T: CustomDebugStringConvertible
{   
  for (item: T) in items {
    stdout.write(item.debugDescription)

CodaFi

// Playground - noun: a place where people can play
// I wouldn't want a pair of birds that were... too demonstrative.


func idiot<A>(a : A) -> A {
	return a
}

func kestrel<A, B>(a : A) -> B -> A {
	return { _ in a }

CodaFi

//
//  Free.swift
//  Swift_Extras
//
//  Created by Robert Widmann on 9/19/14.
//  Copyright (c) 2014 Robert Widmann. All rights reserved.
//

import Foundation

CodaFi

Modular Swift

• Proposal: SE-NNNN
• Authors: Robert Widmann, Jaden Geller
• Review Manager: TBD
• Status: Awaiting review

Introduction

CodaFi

#if canImport(Darwin)
import Darwin
#elseif canImport(Glibc)
import Glibc
#else
#error("unsupported platform")
#endif

/// Core utilities for interacting with IP-based abstractions.
public struct IP {

CodaFi

// cc aviary.m -o aviary -framework Foundation -fobjc-arc && ./aviary
#import <Foundation/Foundation.h>

// use it like lambda(…args…)(…return value…)
#define lambda(...) \
^ (__VA_ARGS__) _lambda_body

#define _lambda_body(...) \
{ return __VA_ARGS__; }

CodaFi

Deprecate @UIApplicationMain and @NSApplicationMain

• Proposal: SE-NNNN
• Authors: Robert Widmann
• Review Manager: TBD
• Status: Awaiting implementation

Introduction

@UIApplicationMain and @NSApplicationMain used to be the standard way for iOS and macOS apps respectively to declare a synthesized platform-specific entrypoint for an app. These functions have since been obsoleted by SE-0281 and the @main attribute, and now represent a confusing bit of duplication in the language. This proposal seeks to deprecate these alternative entrypoint attributes in favor of @main in Swift 5.8, and makes their use in Swift 6 a hard error.

CodaFi

#Every Single Option Under The Sun

• optimization level options
• automatic crashing options
• debug info options
• swift internal options
• swift debug/development internal options
• linker-specific options
• mode options