Mac OS X Leopard - ARCAism

Mac developers have a secret weapon that you’re not going to find in the developer
tools folder. It’s what allows you to do so much with so little, freeing you to think
of all the little things that make Mac applications better for your users. It’s what makes the Mac
the easiest, and yet the most powerful, development platform in the world. It’s our language,
Objective-C, and it has several advantages:
• An innovative syntax makes it far more readable than any other C-like language.
• It is object-oriented, so projects are organized and understandable.
• It is natively compiled, outperforming any interpreted language.
• It has a dynamic runtime, making it is as flexible as a scripting language.
• It augments, rather than replaces, C, letting programmers get close to the machine if
they must.
• It is designed for ease of use, especially Objective-C 2.0.
Objective-C Syntax
Above all else, code must be readable. Elegance, performance, and productivity will follow. The
less time you spend figuring out what you wrote yesterday, the more time you’ll have to work on
it today. The better you can understand what a piece of code is doing, the faster you can add
features and fix bugs. If other programmers can understand your code, they can give you constructive
criticism, making you and your program better.
The first thing people notice about Objective-C is its syntax. Although standard C syntax
remains valid, Objective-C adds new syntax, derived from Smalltalk, the first object-oriented
programming language. Many people are at first wary of this alien syntax, but once they get used
to it, they can’t imagine using anything else. That’s because Objective-C is extremely readable.
Consider this function call in C syntax:
setColor(myObject, 0.4, 0.3, 0.0, 1.0);
CHAPTER
Mac OS X Development:
Objective-C
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You can guess it sets a color, but what do those numbers mean? Are those red, green, blue,
and alpha? Or alpha, red, green, and blue? Or cyan, yellow, magenta, and black? Or luminosity,
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