Objective-C syntax sugar wish list

As I mentioned in my previous post Objective-C is my (current) favourite programming language. But there things that could be improved. Creating immutable collections is a bit verbose, for example. (Although—I suspect—no more so than in for example Java.) It goes like this:

NSArray *array = [NSArray arrayWithObjects:
    @"one", @"two", @"three", nil];

NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys:
    [NSNumber numberWithInteger:1], @"one",
    [NSNumber numberWithInteger:2], @"two",
    [NSNumber numberWithBool:YES], @"true",

However, you don't have to use this syntax for strings. Static strings are created with a special syntax, like so:

NSString *string = @"This is a string";

It would be great if this could be extended to arrays and dictionaries. The syntax would be something like this:

NSArray *array = @[ @"one", @"two", @"three" ];

NSDictionary *dict = @{
    @"one", [NSNumber numberWithInteger:1],
    @"two", [NSNumber numberWithInteger:2],
    @"true", [NSNumber numberWithBool:YES],

(Note that for the dictionary I took the liberty of fixing the argument order so that it makes sense to me.)

Creation of NSNumbers is another area that could benefit from the same trick. Although NSNumber instances can be initialised in lots of different ways, I think this new syntax sugar should concern itself with just three: NSInteger, double and BOOL. We would then get this syntax:

@234    // equivalent to [NSNumber numberWithInteger:234]
@-14    // equivalent to [NSNumber numberWithInteger:-14]
@12.0   // equivalent to [NSNumber numberWithDouble:12.0]
@-0.01  // equivalent to [NSNumber numberWithDouble:-0.01]
@YES    // equivalent to [NSNumber numberWithBool:YES]
@NO     // equivalent to [NSNumber numberWithBool:NO]

The initial dictionary creation example would then simply become:

NSDictionary *dict = @{
    @"one", @1,
    @"two", @2,
    @"true", @YES,

I've filed a feature request with Apple, <rdar://problem/6171253>, I don't expect, much, that this wish is heeded. A man can dream, though; a man can dream…

Update: in 2012, Apple did heed this request and implemented static initialisers for many different types. I only had to wait 4 years :-)

Posted 25 August 2008 Copyright © Stig Brautaset