goopi · December 29, 2015 18:09 · Nov 29, 2013 · Jul 9, 2012
diff --git a/test.m → nsarray-slice.m b/test.m → nsarray-slice.m
diff --git a/test.m b/test.m
@@ -0,0 +1,69 @@
+// clang -framework Foundation -fobjc-arc -O3 test.m
+
+#import <Foundation/Foundation.h>
+
+
+@interface Slice : NSObject
+@property NSInteger start;
+@property NSInteger length;
+@end
+@implementation Slice
+@end
+
+@interface NSNumber (SliceCreation)
+
+- (Slice *): (NSInteger)length;
+
+@end
+
+@implementation NSNumber (SliceCreation)
+
+- (Slice *): (NSInteger)length
+{
+    Slice *slice = [[Slice alloc] init];
+    [slice setStart: [self integerValue]];
+    [slice setLength: length];
+    return slice;
+}
+
+@end
+
+@interface NSArray (Slicing)
+
+- (id)objectForKeyedSubscript: (id)subscript;
+
+@end
+
+@implementation NSArray (slicing)
+
+- (id)objectForKeyedSubscript: (id)subscript
+{
+    Slice *slice = subscript;
+    return [self subarrayWithRange: NSMakeRange([slice start], [slice length])];
+}
+
+@end
+
+int main(int argc, char **argv)
+{
+    @autoreleasepool
+    {
+        NSMutableArray *array = [NSMutableArray array];
+        for(int i = 0; i < 100; i++)
+            [array addObject: @(i * i)];
+
+        NSArray *sliced = array[[@5:8]];
+        NSLog(@"%@", sliced);
+    }
+}
+
+// 2012-07-09 17:15:12.705 a.out[84967:707] (
+//     25,
+//     36,
+//     49,
+//     64,
+//     81,
+//     100,
+//     121,
+//     144
+// )