Improving aggregated data types for performance

For me the most challenging type while implementing RESP in JS was arrays. The input comes as an event with partial data without knowing when the array ends. It would be great to know the actual size of the aggregated data up front similar to bulk strings so it's possible to wait with the parsing until all necessary data has been received. That requires Redis to actually calculate the size up front but the receiver could implement it more efficiently, especially for nested aggregated types. It's off course a trade-off but I believe it could improve the overall performance for these types quite a bit (mainly in case of many entries).

I am curious about your thoughts about this @antirez.