import { MultiMapNonEmpty } from "https://deno.land/x/rimbu@1.0.0/multimap/custom/implementation/base.ts";
Parameters
options: { ifNew?: OptLazy<StreamSource<V>>; ifExists?: (currentValues: TpG["keyMapValuesNonEmpty"]) => StreamSource<V>; }
x/rimbu/multimap/custom/implementation/base.ts>MultiMapNonEmpty#modifyAt
import { MultiMapNonEmpty } from "https://deno.land/x/rimbu@1.0.0/multimap/custom/implementation/base.ts";