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@DougGregor
DougGregor / dynamic_member_lookup_environment.swift
Created May 2, 2018 16:59
Using Swift 4.2's @dynamicMemberLookup to expose environment variables
import Darwin
@dynamicMemberLookup
struct Environment {
subscript(dynamicMember name: String) -> String? {
get {
guard let value = getenv(name) else { return nil }
return String(validatingUTF8: value)
}
@lattner
lattner / async_swift_proposal.md
Last active October 30, 2025 15:46 — forked from oleganza/async_swift_proposal.md
Concrete proposal for async semantics in Swift

Async/Await for Swift

Introduction

Modern Cocoa development involves a lot of asynchronous programming using closures and completion handlers, but these APIs are hard to use. This gets particularly problematic when many asynchronous operations are used, error handling is required, or control flow between asynchronous calls gets complicated. This proposal describes a language extension to make this a lot more natural and less error prone.

This paper introduces a first class Coroutine model to Swift. Functions can opt into to being async, allowing the programmer to compose complex logic involving asynchronous operations, leaving the compiler in charge of producing the necessary closures and state machines to implement that logic.

@dabrahams
dabrahams / ModuleRepl.md
Last active May 18, 2021 00:16
Linking and importing a swift module for use in the REPL
$ echo 'public func f() { print("YES") }' > x.swift
$ swiftc -emit-library -emit-module -module-link-name x  x.swift
$ swift -L . -I .
Welcome to Apple Swift version 5.4 (swiftlang-1205.0.26.9 clang-1205.0.19.55).
Type :help for assistance.
  1> import x
import x
  2> f()
f()
@hollance
hollance / neural.c
Last active April 21, 2023 17:13
Playing with BNNS on macOS 10.12. The "hello world" of neural networks.
/*
The "hello world" of neural networks: a simple 3-layer feed-forward
network that implements an XOR logic gate.
The first layer is the input layer. It has two neurons a and b, which
are the two inputs to the XOR gate.
The middle layer is the hidden layer. This has two neurons h1, h2 that
will learn what it means to be an XOR gate.
@cocoaNib
cocoaNib / exportOptionsAdHoc.plist
Last active July 3, 2025 09:38
Xcode build with exportOptionsPlist
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>method</key>
<string>ad-hoc</string>
</dict>
</plist>
@jakubpetrik
jakubpetrik / handle-signal.swift
Created September 23, 2015 21:34
Signal handling in Swift
/**
http://rosettacode.org/wiki/Handle_a_signal
Most general purpose operating systems provide interrupt facilities, sometimes called signals.
Unhandled signals generally terminate a program in a disorderly manner. Signal handlers are
created so that the program behaves in a well-defined manner upon receipt of a signal.
For this task you will provide a program that displays a single integer on each line of output at
the rate of one integer in each half second. Upon receipt of the SigInt signal (often created by the user typing ctrl-C)
the program will cease printing integers to its output, print the number of seconds the program has run,
@JadenGeller
JadenGeller / AnySet.swift
Created March 30, 2015 22:13
Swift Set of "Any" Type
// Examples
var set = AnySet()
set.insert(3)
set.insert("hello")
set.insert("hi")
set.insert(2.3)
set.contains(6) // -> false
set.contains(3) // -> true
@natecook1000
natecook1000 / NSScanner+Swift.swift
Created March 3, 2015 20:13
Swift-friendly NSScanner methods
// NSScanner+Swift.swift
// A set of Swift-idiomatic methods for NSScanner
//
// (c) 2015 Nate Cook, licensed under the MIT license
import Foundation
extension NSScanner {
// MARK: Strings
@seanlilmateus
seanlilmateus / channel.swift
Last active November 22, 2017 14:02
swift Go like channels
import Foundation
// Playground - noun: a place where people can play
class Channel<T> {
var stream: Array<T>
let queue: dispatch_queue_t
let semaphore: dispatch_semaphore_t
init() {
self.stream = []
@jessepeterson
jessepeterson / app_map.c
Last active October 23, 2023 07:32
_CFPreferencesCopyApplicationMap example
/* re-implementation of the behaviour that the /usr/bin/defaults application
* uses to read sandboxed preference data */
#include <CoreFoundation/CoreFoundation.h>
#define EX_BUNDLE_ID "com.apple.mail"
#define EX_KEY "JunkMailBehavior"
// undocumented, internal CFPreferences API call
extern CFDictionaryRef _CFPreferencesCopyApplicationMap(CFStringRef userName, CFStringRef hostName);