bakul's point is that it's not already implemented--Go's existing map doesn't have finegrained synchronization, and you can't write a generic map that does. Or

bakul's point is that it's not already implemented--Go's existing map doesn't have finegrained synchronization, and you can't write a generic map that does. Or, for another example, you can't write a generic LinkedHashMap, which is a weird data structure that allows you to write constant time LRU caches, and which I presume Go doesn't have.