That syntax works for records not objects. The {< _ = _ >} syntax is sort-of equivalent except it can only be used within method definitions (!) and is therefor

That syntax works for records not objects. The {< _ = _ >} syntax is sort-of equivalent except it can only be used within method definitions (!) and is therefore too restricted. Instead, try taking a look at the store-comonad mechanism I've got below: https://news.ycombinator.com/item?id=9213482 https://news.ycombinator.com/item?id=9213482