Question

In Javascript, for example, you can get the arity (the number of arguments a function is supposed to take) by simply func.length. How can I get this information for a method in Objective-C?

Answer 1

NSMethodSignature is awesome for all kind of reflection information.

SEL selector = @selector(foo:);
NSMethodSignature *sig = [someObj methodSignatureForSelector:selector]
int argCount = [sig numberOfArguments];