Mac OS X Leopard - ARCAism

Syntax Coloring
As you type, Xcode analyzes the syntax of your code and automatically colors the text based on
what it represents. While the colors can be set to your personal preference, by default, keywords
are pink, macros are brown, comments are green, numerical constants are blue, and string constants
are red.
Since your code remains black, the colors help it stand out. It also helps you keep your
strings and comments properly closed. If, for example, you forget to type a closing quotation
mark, the bright pink color of your code will both indicate that something’s wrong and give you
an immediate idea of where the problem is.
Automatic Formatting
While whitespace remains optional in most languages, no programmer I’ve ever met would consider
forgoing it. Xcode will automatically indent your code, and if you like, will even insert
closing braces for you. Aside from keeping your code tidy and preventing premature wear on
your Tab key, automatic formatting is another trick to help you notice mistakes early. Forgetting
a brace or bracket will cause subsequent lines to format improperly.
Autocompletion
Terseness is the enemy of readability, but descriptive variable and function names take longer to
type, cramping a coder’s mind and hands. Autocompletion combines the best of both worlds.
Typing just a few letters can produce descriptive, readable code. Autocompletion further saves
time by inserting replaceable argument tokens in method names. Typing Cmd+/ will highlight the
next token.
Again, this convenience also prevents errors. Assuming you pick the correct completion, the
expanded text will always be correct, while typing out the entire name by hand is prone to
human error. It’s a good habit to always activate autocompletion, even when you’ve typed something
out, just to make sure you didn’t make a mistake.
The autocompletion suggestions list can be activated by pressing Esc. From Xcode’s preference
window, you can also choose to have autocompletion occur automatically if you pause
while typing. Since that could quickly become annoying, the length of the pause is also customizable.
Code Scoping
Xcode 3 introduces a ribbon bar that runs alongside the main code editing window. The ribbon
shows varying shades of gray depending on the scope of the code beside it. This gives a quick
visual check that all your braces and brackets are properly balanced. If you need a little extra
indication, hovering your cursor above the ribbon will extend its shading to the code itself,
giving an exact indication of scope.
Code Folding
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Xcode 3 also introduces code folding, which collapses a given scope in the editor. For example, a
long if statement that doesn’t apply to what you’re trying to do can be collapsed into a single
line. Similarly, functions and sections can be collapsed. The collapsing is syntax aware, and if
you use the line numbering bar, the appropriate numbers will be skipped so you don’t lose your
place.
To fold your code, click the ribbon bar. When code is folded, a disclosure triangle will
appear in the ribbon bar. Clicking this disclosure triangle will unfold that section of code.