The standard Cocoa method for a string with multiple replacements is [NSString stringWithFormat:]. To build a standard analogy string from the SATs:

	hand : palm :: foot : sole

you would break out each of the replaceable elements into separate strings and replace them in the format string with the placeholder ‘%@’. (There are many other format specifiers–look up printf()–but ‘%@’ is very common in Cocoa since it specifies an Objective-C object, not just a simple number or C null-terminated string.)

	NSString * format = @"%@ : %@ :: %@ : %@";

To create the desired string:

	NSString * myString =
	   [NSString stringWithFormat:format,
	                              @"hand",
	                              @"palm",
	                              @"foot",
	                              @"sole",
	                              nil];

If you want to create a different analogy string, just call stringWithFormat: again, using the same format string but different parameters following it.

The stringWithFormat: method takes a list of objects, and the nil parameter indicates the end of the list. If you want to manage the list of substitution parameters, though, you shouldn’t need that nil since NSArray knows how many elements it contains. Unfortunately, there isn’t a method like stringWithFormat: which takes an NSArray instead of a list of objects; there also doesn’t seem to be a simple way to convert the contents of an NSArray to a nil-terminated parameter list.

How then can you make this templating more dynamic at runtime by storing the list in an NSArray?

(Read the article)

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Well, here we go…

Corporation Unknown will serve to track the course of my progress to an intended career as an independent Mac software developer. No, I don’t hate my job (even though it’s not Mac development), but I do feel that this is the long-term path to my career happiness and further success. We will track milestones on the way to launch, and share insights gained along the way–both in business and code.

Obviously, there is a product planned; it’s not Web 2.0, and it’s not going to change the world as you know it (in version 1.0, at least). It will be easier to use than what’s out there, yet more powerful at the same time–and I already have plans for more powerful future versions.

Let us begin…

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