concrete subclass of NSArray with Type filtering
What you can import: you will need to declare an interface and an implementation for each filtering class
#import "TypedArray.h"
TYPED_ARRAY_INTERFACE(NSString)
TYPED_ARRAY_IMPLEMENTATION(NSString)
What you can create: anything like a normal NSArray
// this will produce an NSStringArray with only @"foo" and @"bar"
NSStringArray *myArray = [NSStringArray arrayWithObjects:@"foo", @(true), @"bar", @[], nil];