@thi.ng/parse/combinators/check.js

Purely functional parser combinators & AST generation for generic inputs

import { parseError } from "../error.js";
import { xform } from "./xform.js";
const check = (parser, pred, msg = "check failed") => xform(
  parser,
  (scope, ctx) => pred(scope) ? scope : parseError(ctx, msg)
);
export {
  check
};