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@ole
ole / swift-has-feature.sh
Last active November 21, 2024 10:32
swift-list-feature: List Swift compiler upcoming and experimental feature flags. ★ swift-has-feature: Check if a given compiler knows a specific feature flag, and whether it's an upcoming or experimental flag.
#!/bin/zsh
# Test if the Swift compiler knows about a particular language feature.
#
# Usage:
#
# swift-has-feature [--swift SWIFT_PATH] [--language-version LANGUAGE_VERSION] FEATURE
#
# The feature should be an upcoming or experimental language feature,
# such as `"StrictConcurrency"` or `"ExistentialAny"`.
@fernandoaleman
fernandoaleman / mysql2-apple-silicon-macos-sonoma.md
Created November 2, 2023 16:32
How to install mysql2 gem on apple silicon M1, M2 or M3 macOS Sonoma

Problem

Installing mysql2 gem errors on Apple silicon M1, M2 or M3 Mac running macOS Sonoma.

Solution

Make sure mysql-client, openssl and zstd are installed on Mac via Homebrew.

Replace mysql-client with whichever mysql package you are using

@soffes
soffes / Readme.markdown
Created July 3, 2018 23:25 — forked from calebd/Readme.markdown
Run Loop Source

CFRunLoopSource is cool. It lets you build behavior similar to the mechanisms that drive setNeedsLayout and setNeedsDisplay in UIKit.

I found myself in need of something like this a couple of times. It's great to know that no matter how many times I say I need to update something, I will get a single callback at the end of the run loop that gives me a chance to perform my work.

Here is a little Swift wrapper that makes the API easier to deal with.


Updated for Swift 4

@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 December 17, 2024 16:54
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

@calebd
calebd / Readme.markdown
Last active September 7, 2022 16:45
Run Loop Source

CFRunLoopSource is cool. It lets you build behavior similar to the mechanisms that drive setNeedsLayout and setNeedsDisplay in UIKit.

I found myself in need of something like this a couple of times. It's great to know that no matter how many times I say I need to update something, I will get a single callback at the end of the run loop that gives me a chance to perform my work.

Here is a little Swift wrapper that makes the API easier to deal with.

@jspahrsummers
jspahrsummers / GHRunLoopWatchdog.h
Created January 28, 2015 20:50
A class for logging excessive blocking on the main thread
/// Observes a run loop to detect any stalling or blocking that occurs.
///
/// This class is thread-safe.
@interface GHRunLoopWatchdog : NSObject
/// Initializes the receiver to watch the specified run loop, using a default
/// stalling threshold.
- (id)initWithRunLoop:(CFRunLoopRef)runLoop;
/// Initializes the receiver to detect when the specified run loop blocks for
@peeblesjs
peeblesjs / gist:9288f79322ed3119ece4
Last active February 11, 2016 23:31
A naive "valueForKey:" operator in Swift
operator infix --> {}
func --> (instance: Any, key: String) -> Any? {
let mirror = reflect(instance)
for index in 0 ..< mirror.count {
let (childKey, childMirror) = mirror[index]
if childKey == key {
return childMirror.value
}
}
@kristopherjohnson
kristopherjohnson / MustacheRenderer.java
Created July 3, 2013 16:37
Configure JMustache to work like GRMustache, to allow the same Mustache templates to be used on iOS and Android
package net.kristopherjohnson.mustache;
// from jmustache-1.8.jar
import com.samskivert.mustache.Mustache;
/**
* Convenience class wrapper around the functionality provided by the JMustache library.
*
* Wherever possible, the template rendering behavior is configured to be compatible with the
* GRMustache library, so that the same templates can be used on iOS and Android.
@piscisaureus
piscisaureus / pr.md
Created August 13, 2012 16:12
Checkout github pull requests locally

Locate the section for your github remote in the .git/config file. It looks like this:

[remote "origin"]
	fetch = +refs/heads/*:refs/remotes/origin/*
	url = [email protected]:joyent/node.git

Now add the line fetch = +refs/pull/*/head:refs/remotes/origin/pr/* to this section. Obviously, change the github url to match your project's URL. It ends up looking like this: