###FoundationRaise.h

On MacOS X, the header NSRaise.h provides several macros for preformatted exceptions that are commonly raised by frameworks:

• Abstract method invocation
• Unimplemented method
• Unimplemented function

These do not exist as part of the iOS SDK. FoundationRaise.h provides equivalents for these macros so your iOS projects can be written to raise the expected exceptions.

###Usage

Include the header: #import "FoundationRaise.h"

Using the macros is simple, and they are self-contained.

A common and powerful design pattern in Objective-C is the class cluster. A class cluster groups a number of private, concrete subclasses under a public abstract superclass. Primitive methods of the superclass are abstract, and typically throw exceptions when invoked directly.

Using an abstract method as an example, your implemention would be:

- (BOOL) canFormVoltron {
	NSInvalidAbstractInvocation();
	return NO;
}

This will raise the exception when called:

caught "NSInvalidArgumentException", "-canFormVoltron only defined for abstract class. Define -[SomeClass canFormVoltron]

Using NSUnimplementedMethod() and NSUnimplementedFunction() is similar.