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Methods

 To define a new method, simply put its implementation in the script file. You don't need to declare it ahead of time. For example, this is the definition of a method from the Main component in the Visitors example:

	- recordMe {
		if ([aName length]) {
			[[self application] setLastVisitor:aName];	
			[self setAName:@""]; // clear the text field
		}
	}
Methods can take arguments. To define a method that takes arguments, you place the argument name after a colon (:). For example, the following method takes two arguments. It adds the two arguments together and returns the result:

	- addFirstValue:firstValue toSecondValue:secondValue {
		id result;
		result = firstValue + secondValue;
		return result;
	}
The strings that appear to the left of the colons are part of the method name. The method above is named addFirstValue:toSecondValue:. It takes two arguments, which it calls firstValue and secondValue.

If you want, you can add type information for the return values and parameter values. For example, the following method, subtractFirstValue:fromSecondValue:, subtracts one number from another and returns the result:

	- (NSNumber *)subtractFirstValue:(NSNumber *)firstValue 
	fromSecondValue:(NSNumber *)secondValue {
		NSNumber *result;
		result = secondValue - firstValue;
		return result;
	}
In these examples, note the following:

Both example methods return a value, stored in result. If a method doesn't return a meaningful value, you don't have to include a return statement (and, as stated above, even if a method returns no value you shouldn't declare it as returning void).

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