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@chriseidhof
chriseidhof / helloworld.swift
Created May 28, 2018 13:58
NIO Hello World
import Foundation
import NIO
import NIOHTTP1
// Inspired/parts copied from http://www.alwaysrightinstitute.com/microexpress-nio/
final class HelloHandler: ChannelInboundHandler {
typealias InboundIn = HTTPServerRequestPart
func channelRead(ctx: ChannelHandlerContext, data: NIOAny) {
name download_total
AFNetworking 61983241
Fabric 50998892
Crashlytics 49667729
SDWebImage 45471101
Alamofire 42097177
CocoaLumberjack 36071914
Bolts 35294870
FirebaseInstanceID 30277793
FirebaseAnalytics 30254593

why doesn't radfft support AVX on PC?

So there's two separate issues here: using instructions added in AVX and using 256-bit wide vectors. The former turns out to be much easier than the latter for our use case.

Problem number 1 was that you positively need to put AVX code in a separate file with different compiler settings (/arch:AVX for VC++, -mavx for GCC/Clang) that make all SSE code emitted also use VEX encoding, and at the time radfft was written there was no way in CDep to set compiler flags for just one file, just for the overall build.

[There's the GCC "target" annotations on individual funcs, which in principle fix this, but I ran into nasty problems with this for several compiler versions, and VC++ has no equivalent, so we're not currently using that and just sticking with different compilation units.]

The other issue is to do with CPU power management.

@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)
}
@tclementdev
tclementdev / libdispatch-efficiency-tips.md
Last active July 8, 2025 03:48
Making efficient use of the libdispatch (GCD)

libdispatch efficiency tips

The libdispatch is one of the most misused API due to the way it was presented to us when it was introduced and for many years after that, and due to the confusing documentation and API. This page is a compilation of important things to know if you're going to use this library. Many references are available at the end of this document pointing to comments from Apple's very own libdispatch maintainer (Pierre Habouzit).

My take-aways are:

  • You should create very few, long-lived, well-defined queues. These queues should be seen as execution contexts in your program (gui, background work, ...) that benefit from executing in parallel. An important thing to note is that if these queues are all active at once, you will get as many threads running. In most apps, you probably do not need to create more than 3 or 4 queues.

  • Go serial first, and as you find performance bottle necks, measure why, and if concurrency helps, apply with care, always validating under system pressure. Reuse

@gregomni
gregomni / count.swift
Created April 20, 2018 18:08
Array counts in the type system...
protocol Counted {
associatedtype More : Counted
associatedtype Less : Counted where Self.More.Less == Self
}
struct CountedArray<T, C: Counted> {
var array: [T]
init(array: [T] = []) {
self.array = array
@lsavino
lsavino / compilation-optimization.md
Last active July 27, 2022 17:44
Compiler Optimizations, Compiling Optimally, and Whole Modules

DEPRECATED for Xcode 10 🎈

(check out What's New in Swift at 11:40, slide 42)

Whole Module Compilation Optimizations: Why these terms are sometimes misleading

When you look up how to compile swift faster for debug builds, people very earnestly give advice that seems contradictory: you should "try using the whole module optimization flag," and also "never use whole module optimization for debugging". [^1]

This is confusing because some of us are using these two general words:

compilation: "turning text into an executable program"

@damienlaughton
damienlaughton / UIAccessorizedTextField.swift
Created March 28, 2018 15:16
UIAccessorizedTextField is an iOS friendly alternative to the drop down list
//
// UIAccessorizedTextField.swift
// AccessorizedTextField
//
// Created by Damien Laughton on 28/03/2018.
// 2018 Mobilology Limited. No rights reserved.
//
import Foundation
import UIKit
@anandabits
anandabits / ClosedProtocol.swift
Created February 11, 2018 21:30
Emulating closed protocols in Swift
// This example shows how closed protocols can be emulated in Swift today.
// The technique leverages Swift's support for public (but not open) classes.
// First, it's worth observing that there is an almost trivial technique that can be used when
// it is possible to specify a (possibly abstract) superclass for all conforiming types.
// Simply declare a public (not open) base class and a protocol with a Self inheritance constraint.
// Swift does not support open subclasses of a public superclass so no classes outside the module
// will be able to meet the self inheritance constraint.
public class FooBase {}
public protocol Foo where Self: FooBase {}
@ian-mcdowell
ian-mcdowell / Info.plist
Last active February 14, 2022 11:13
Keynote DAVFileProvider
<?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>CFBundleName</key>
<string>KeynoteDAVFP</string>
<key>CFBundleIdentifier</key>
<string>com.apple.Keynote.KeynoteDAVFP</string>
<key>CFBundleDisplayName</key>
<string>WebDAV</string>