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@airspeedswift
airspeedswift / GenericInfProb.swift
Last active August 29, 2015 14:07
Swift for…in generic inference prob
// original version with problem
struct A<T> {
func f<S: SequenceType where S.Generator.Element == T>(s: S) {
// error: cannot convert expression's type S to type S
for v in s {
print(v)
}
}
}
@tomlokhorst
tomlokhorst / Optional+Unwrap.swift
Last active December 26, 2017 19:50
Unwrap multiple optionals in Swift 1.0
func unwrap<T1, T2>(optional1: T1?, optional2: T2?) -> (T1, T2)? {
switch (optional1, optional2) {
case let (.Some(value1), .Some(value2)):
return (value1, value2)
default:
return nil
}
}
func unwrap<T1, T2, T3>(optional1: T1?, optional2: T2?, optional3: T3?) -> (T1, T2, T3)? {
@davbeck
davbeck / WKUIDelegate.m
Last active September 28, 2023 06:59
Boilerplate implementation of WKUIDelegate to support Javascript alerts.
#pragma mark - WKUIDelegate
- (void)webView:(WKWebView *)webView runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)())completionHandler
{
UIAlertController *alert = [UIAlertController alertControllerWithTitle:nil
message:message
preferredStyle:UIAlertControllerStyleAlert];
[alert addAction:[UIAlertAction actionWithTitle:NSLocalizedString(@"OK", nil) style:UIAlertActionStyleCancel handler:^(UIAlertAction *action) {
completionHandler();
@mattdenner
mattdenner / gist:dd4cfde3f355ff6b7be8
Last active May 18, 2016 18:52
From imperative to functional: functors, applicatives, monads & other link bait

I’ve been writing a load of Swift code recently for work and this has lead me into the world of typed functional programming. The app needs to build certain objects from a comma separated string, and this lead me to applicative functors, which lead me to brain ache but enlightenment. So here’s my thoughts on how I got to understand these a little better.

All of the code is in Swift, so less clean than Haskell. I’m also only a about 6 weeks into Swift development so I probably haven’t got all of the idioms right. I’ve avoided the optional shorthand wherever possible here, preferring Optional<Type> over Type? because I believe the latter is hiding something that helps understand this code in the context of other generic classes.

It’s also long! I think it’s probably the longest blog post I’ve ever written but I found it interesting and useful, for myself, to write. If you’re one of those people who skip to the end of a book to find out whodunit then I’ve included

@andymatuschak
andymatuschak / gist:2b311461caf740f5726f
Created December 28, 2014 18:17
A pragmatic and intentionally non-abstract solution to JSON decoding / initialization that doesn't require learning about five new operators.
struct User {
let id: Int
let name: String
let email: String?
}
extension User: JSONDecodable {
static func create(id: Int, name: String, email: String?) -> User {
return User(id: id, name: name, email: email)
}
@langford
langford / gist:68b86eb3ee274f426f35
Created January 30, 2015 20:03
Doing IPA builds from the command line because you're tired of the lack of repeatability in Xcode Adhoc builds
#!/bin/sh
# Current as working as of 2014/09/22
# modified form of http://stackoverflow.com/questions/25056144/xcode-6-how-to-pick-signing-certificate-provisioning-profile-for-ad-hoc-distri
# Xcode 6
MYAPP="HELLOWORLD"
OUTPUTDIR="$HOME/Desktop/$MYAPP"
APPNAME="ANAppName"
SCHEME="ASchemeName"
@macguru
macguru / gist:b7a01e3f0e9ae6f350d5
Last active May 10, 2020 20:58
Interface sizes a regular Universal app must support with iOS 11 when supporting all devices. Starts with iPhone 5 and goes up to iPad Pro 12.9".
COMPACT WIDTH (stacked view)
- 320 x 568 pt
-> iPhone 5, 5s
- 320 x 768 pt
-> iPad 9.7" Split Landscape 2/3 right
- 320 x 834 pt
-> iPad 10.5" Split Landscape 2/3 right
- 320 x 1024 pt
-> iPad 9.7" Split Portrait right
@createuniverses
createuniverses / cxxforth-win.cpp
Created February 23, 2016 04:02
cxxforth modified so it compiles with VS2010
/****
cxxforth: A Simple Forth Implementation in C++
==============================================
by Kristopher Johnson
<https://github.com/kristopherjohnson/cxxforth>
----
@andymatuschak
andymatuschak / States-v3.md
Last active May 12, 2025 06:11
A composable pattern for pure state machines with effects (draft v3)

A composable pattern for pure state machines with effects

State machines are everywhere in interactive systems, but they're rarely defined clearly and explicitly. Given some big blob of code including implicit state machines, which transitions are possible and under what conditions? What effects take place on what transitions?

There are existing design patterns for state machines, but all the patterns I've seen complect side effects with the structure of the state machine itself. Instances of these patterns are difficult to test without mocking, and they end up with more dependencies. Worse, the classic patterns compose poorly: hierarchical state machines are typically not straightforward extensions. The functional programming world has solutions, but they don't transpose neatly enough to be broadly usable in mainstream languages.

Here I present a composable pattern for pure state machiness with effects,

@cocoalabs
cocoalabs / gist:2fb7dc2199b0d4bf160364b8e557eb66
Created August 15, 2016 21:50
Color Terminal for bash/zsh etc..
man() {
env \
LESS_TERMCAP_mb=$(printf "\e[1;31m") \
LESS_TERMCAP_md=$(printf "\e[1;31m") \
LESS_TERMCAP_me=$(printf "\e[0m") \
LESS_TERMCAP_se=$(printf "\e[0m") \
LESS_TERMCAP_so=$(printf "\e[1;44;33m") \
LESS_TERMCAP_ue=$(printf "\e[0m") \
LESS_TERMCAP_us=$(printf "\e[1;32m") \
man "$@"