import { mergeSecond } from "https://deno.land/x/fun@v2.0.0/pair.ts";
Apply a function in the first position of a pair to a value in the second position of a pair.
Examples
Example 1
Example 1
import * as P from "./pair.ts";
import { flow } from "./fn.ts";
const double = flow(
P.dup<number>,
P.mapSecond(n => (m: number) => n + m),
P.mergeSecond,
);
const result1 = double(1); // 2
const result2 = double(2); // 4