@thi.ng/transducers-async/step.js

Async versions of various highly composable transducers, reducers and iterators

import { isReduced } from "@thi.ng/transducers/reduced";
import { ensureAsyncTransducer } from "./ensure.js";
import { push } from "./push.js";
const step = (tx, unwrap = true) => {
  const [_, complete, reduce] = ensureAsyncTransducer(tx)(push());
  let done = false;
  return async (x) => {
    if (!done) {
      let acc = await reduce([], x);
      done = isReduced(acc);
      if (done) {
        acc = await complete(acc.deref());
      }
      return acc.length === 1 && unwrap ? acc[0] : acc.length > 0 ? acc : void 0;
    }
  };
};
export {
  step
};