Nick Lockwood nicklockwood

Suppose you have a network method that only uses a single block callback

typedef void (^Handler)(BOOL success, id response, NSError *error);

- (void)makeRequestWithHandler:(Handler)handler;

But you have to make this request dozens of times, and you want to reuse the same failure handler in most cases? Easy, just have a factory function that returns a block:

typedef void (^SuccessHandler)(id response);

typedef void (^ErrorHandler)(NSError *error);

Storyboard Segues initially seem like a pretty cool way to construct interfaces using minimal glue code. But actually, ordinary nibs already support this, and in a much more flexible way.

Certainly, a Storyboard lets you bind a button action up to display a view controller with no code, but in practice you will usually want to pass some data to the new controller, depending on which button you used to get there, and this means implementing the -prepareForSegue:sender: method, which rapidly becomes a giant if/elseif statement of doom, negating most of the benefit of the codeless segue:

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if ([segue.identifier isEqualToString:@"modalSegue"])
    {
        ModalViewController *controller = (ModalViewController *)segue.destination;

controller.someProperty = someValue;

Method

- (void)addObserver:(id)observer
            forName:(NSString *)name
             object:(id)object
              queue:(NSOperationQueue *)queue
         usingBlock:(void (^)(NSNotification *note, __weak id observer))block;

Usage

It's Impossible

I have reluctantly come to accept that it is impossible to create a "perfect" programming language. Every language is domain-specific in some sense, and many of the criteria that make a language good for one purpose are fundamentally in opposition to qualities that are good for another.

A classic example would be "scripting" languages versus "embedded" languages.

Good qualities in a scripting language are:

Dynamic typing (no need to specify types, or cast between them)

	//
	// ARC Helper
	//
	// Version 2.2
	//
	// Created by Nick Lockwood on 05/01/2012.
	// Copyright 2012 Charcoal Design
	//
	// Distributed under the permissive zlib license
	// Get the latest version from here:

	@implementation UINavigationBar (CustomBackground)

	- (UIImage *)barBackground
	{
	return [UIImage imageNamed:@"top-navigation-bar.png"];
	}

	- (void)didMoveToSuperview
	{
	//iOS5 only

	//Interface

	@interface NSObject (Evil)

	@property (readonly) BOOL (^equals)(id object);

	@end


	@interface NSArray (Evil)

	NSURLrequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"http://example.com/file.json"]];
	[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse response, NSData data, NSError *error) {
	id jsonObject = [NSJSONSerialization JSONObjectWithData:data options:0 error:NULL];
	}];

	@interface FCURL : NSObject

	@property (nonatomic, copy) NSString *absoluteString;

	@end

	@implementation NSURL (FastCoding)

	- (Class)classForCoder
	{

	#import <UIKit/UIKit.h>
	#import <objc/runtime.h>


	@implementation NSCache (Fix)

	+ (void)load
	{
	//swizzle init
	Method a = class_getInstanceMethod(self, @selector(init));