Premappable

import type { Premappable } from "https://github.gh-proxy.cn/raw.githubusercontent.com/baetheus/fun/main/premappable.ts";

A Premappable structure has the method premap.

interface Premappable extends Mappable, Hold {

readonly dimap: <A, D, I, L>(fld: (l: L) => D, fai: (a: A) => I) => (ua: $<U, [A, B, C], [D], [E]>) => $<U, [I, B, C], [L], [E]>;

readonly premap: <L, D>(fia: (l: L) => D) => <A, B, C, E>(ua: $<U, [A, B, C], [D], [E]>) => $<U, [A, B, C], [L], [E]>;

}

§Type Parameters

U extends Kind

readonly dimap: <A, D, I, L>(fld: (l: L) => D, fai: (a: A) => I) => (ua: $<U, [A, B, C], [D], [E]>) => $<U, [I, B, C], [L], [E]>

readonly premap: <L, D>(fia: (l: L) => D) => <A, B, C, E>(ua: $<U, [A, B, C], [D], [E]>) => $<U, [A, B, C], [L], [E]>