Return of the Objective-C Jedi

Luke's First Lightsaber

[[[ These ]]] are your father's square brackets, the weapons of a Jedi Knight.
Not as clumsy or random as C++.
Elegant weapons for a more civilized age.

What's Different in Mulle-ObjC

This is like Objective-C circa 2010(?), good but not fully baked. Far better than circa 1986-2009, when it was a very thin translation layer over C.

  • No ARC (Automatic Reference Counting). This is just invisible sugar to hide retain/release/autorelease, and while ARC's convenient, it's trivial if you actually know how reference counting works. Don't really miss it.
  • No dot property syntax. [[myObj name] length] instead of myObj.name.length, and [myObj setName:newName] instead of myObj.name = newName. I can live with it, but I really did like dot syntax, even if it does "overload" the . operator and hide the distinction between methods and variables.
    • When dot syntax came out, Objective-C nerds came close to fistfights over this. You would not believe the venom some people had for it. Most of those nerds died or quit or got old & tired before fucking Swift came around, I guess.
  • No array syntax. [myList objectAtIndex:i] instead of myList[i]. This is a pain in the ass, I'll have to write some shorthand macros (or rather, go dig them out of my very oldest code).
  • No blocks. This one hurts, but it's a reasonable pick-your-battles decision. Classic: Write a method, dispatch to it, and call back success somehow. Blocks: create a weakSelf reference, enclose it, search-replace self in your block, pick one of a half-dozen complex GCD methods, get a memory leak because you retained something across the block boundary. This is annoying but logically simpler:
    [self performSelectorInBackground:@selector(computeData) withObject:inputData];
    
    - (void)computeData:(id)inputData {
        // create outputData
        [self setOutputData:outputData];
        [[NSNotificationCenter defaultCenter] postNotification:NOTI_DataComputed];
    }
    
  • Has object literals: @42 and @(var) create an NSNumber, @[] creates an NSArray, @{} creates an NSDictionary; dicts use key:value order, not the reverse order used in -[NSDictionary dictionaryWithObjectsAndKeys:], and array and dicts don't need a trailing nil, which was a constant source of mystifying bugs back in the day. Big win!
    • Hmn, crashes if you do something janky like [@[] mutableCopy]: mulle_objc_universe 0x1006adef0 fatal: unknown method 5e1b0403 "-getObjects:range:" in class 7aa0d636 "_MulleObjCEmptyArray"
  • Has for (id x in container) loops, using NSFastEnumeration. The 1.0 process of looping enumerations was awful, so this is very nice.
  • Huh, does have @autoreleasepool, so maybe I should use that instead of NSAutoreleasePool like a caveman? It compiles and seems to work.
  • Properties have properties assign/retain nonatomic/atomic nonnullable readonly, default is assign nonatomic, no "nullable" or "readwrite" flags needed. As it should be.
  • Weird isa define instead of pointer: blog post

TODO

  • I haven't set up an NSRunLoop or the equivalent of NSApplication (which is in AppKit, not Foundation), need to do that and then I'll have a working app template.

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