or | /mod.ts | pazza@v0.3.0

Parser combinators library designed for Deno, but also works on browsers and Node.js.

function or

import { or } from "https://deno.land/x/pazza@v0.3.0/mod.ts";

or<L, R, E, I extends Input, CtxIn, CtxOut>(left: IParser<L, unknown, I, CtxIn, CtxOut>, right: IParser<R, E, I, CtxIn, CtxOut>): IParser<L | R, E, I, CtxIn, CtxOut>

Attempt to run "left" parser at first. If it succeeds, return its result. If it fails, run "right" parser.

or(digit(), alpha())("4").output === "4";
or(digit(), alpha())("a").output === "a";
or(digit(), alpha())("").ok === false;

Type Parameters

I extends Input

CtxIn

CtxOut

left: IParser<L, unknown, I, CtxIn, CtxOut>

left parser

right parser