Belt_HashMapStringlet make: hintSize:int => t('b);let clear: t('b) => unit;let isEmpty: t(_) => bool;setDone tbl k v if k does not exist, add the binding k,v, otherwise, update the old value with the new v
let forEachU: t('b) => Js.Fn.arity2((key => 'b => unit)) => unit;let reduceU: t('b) => 'c => Js.Fn.arity3(('c => key => 'b => 'c)) => 'c;let keepMapInPlaceU: t('a) => Js.Fn.arity2((key => 'a => option('a))) => unit;let size: t(_) => int;let valuesToArray: t('a) => array('a);let getBucketHistogram: t(_) => array(int);let logStats: t(_) => unit;