Method overloading in Objective-C?

Question

As far as my knowledge, Objective-C does not support method overloading. What can be the alternative for this in Objective-C? Or should I always use different method name?

Answer 1

Correct, objective-C does not support method overloading, so you have to use different method names.

Note, though, that the "method name" includes the method signature keywords (the parameter names that come before the ":"s), so the following are two different methods, even though they both begin "writeToFile":

-(void) writeToFile:(NSString *)path fromInt:(int)anInt; -(void) writeToFile:(NSString *)path fromString:(NSString *)aString; 

(the names of the two methods are "writeToFile:fromInt:" and "writeToFile:fromString:").

Answer 2

It may be worth mentioning that even if Objective-C doesn't support method overloading, Clang + LLVM does support function overloading for C. Although not quite what you're looking for, it could prove useful in some situations (for example, when implementing a slightly hacked (goes against encapsulation) version of the visitor design pattern)

Here's a simple example on how function overloading works:

__attribute__((overloadable)) float area(Circle * this) {     return M_PI*this.radius*this.radius; }  __attribute__((overloadable)) float area(Rectangle * this) {     return this.w*this.h; }  //... //In your Obj-C methods you can call: NSLog(@"%f %f", area(rect), area(circle));