Comment by 0x62c1b43e

It’s not the only one. Some other packages that used workarounds like interface{} or other things to work around the lack of generics were container/{heap,list,ring}, sort, golang.org/x/sync/singleflight, /x/exp/{maps,slices}, etc. And people will want to write their own patterns at other times of course too. It wouldn’t be reasonable for these all to become builtin types like map. These standard library packages that already exist will also become more efficient and potentially reduce allocations (when using primitives) as well.