import { option } from "https://deno.land/x/fun@v2.0.0/mod.ts";
const { fold } = option;
Reduce over an Option. Since an Option contains at most one value this function operates a lot like getOrElse. If the passed option is None then it returns the initial value, otherwise the foldr function is called with both the initial value and the inner A.
Examples
Example 1
Example 1
import * as O from "./option.ts";
const fold = O.fold((n: number, m: number) => n + m, 0);
const result1 = fold(O.some(1)); // 1
const result2 = fold(O.none); // 0