method NonLeafBlock.prototype.updateAtRe-exportimport { NonLeafBlock } from "https://deno.land/x/rimbu@0.14.1/list/custom/index.ts"; updateAt(index: number, update: Update<T>): NonLeafBlock<T, C>Parametersindex: numberupdate: Update<T>ReturnsNonLeafBlock<T, C>