Belt_internalBucketsTypetype 'a opt = 'a Js.undefinedtype ('hash, 'eq, 'c) container = {mutable size : int;mutable buckets : 'c opt array;hash : 'hash;eq : 'eq;}val toOpt : 'a opt -> 'a optionval return : 'a -> 'a optval emptyOpt : 'a Js.undefinedval make : hash:'hash -> eq:'eq -> hintSize:int -> ('hash, 'eq, _) containerval clear : (_, _, _) container -> unitval isEmpty : (_, _, _) container -> bool