soffes

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

import Darwin

@dynamicMemberLookup
struct Environment {
  subscript(dynamicMember name: String) -> String? {
    get {
      guard let value = getenv(name) else { return nil }

      return String(validatingUTF8: value)
    }

tclementdev

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

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

/// 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

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

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

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 = git@github.com: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:

gabrielstuff

// {{#each_with_index records}}
//  <li class="legend_item{{index}}"><span></span>{{Name}}</li>
// {{/each_with_index}}

Handlebars.registerHelper("each_with_index", function(array, fn) {
  var total = array.length;
  var buffer = "";
  for (var i = 0, j = array.length; i < j; i++) {
    var item = array[i];

burin

Handlebars.registerHelper 'each_with_index', (array, fn) ->
  buffer = ''
  for i in array
    item = i
    item.index = _i
    buffer += fn(item)
  buffer