gistfile1.m

    var string = @"/a/b";
  	var selector =  @selector(lastPathComponent);
 
    var invocation = [CPInvocation invocationWithMethodSignature:nil];
    [invocation setTarget:string];
    [invocation setSelector:selector];
  
  	var result = [invocation invoke];
    
     CPLogConsole("RESULT = "+ result);