@thi.ng/transducers/duplicate.js

Collection of ~170 lightweight, composable transducers, reducers, generators, iterators for functional data transformations

import { isIterable } from "@thi.ng/checks/is-iterable";
import { compR } from "./compr.js";
import { iterator } from "./iterator.js";
import { isReduced } from "./reduced.js";
function duplicate(n = 1, src) {
  return isIterable(src) ? iterator(duplicate(n), src) : (rfn) => {
    const r = rfn[2];
    return compR(rfn, (acc, x) => {
      for (let i = n; i >= 0 && !isReduced(acc); i--) {
        acc = r(acc, x);
      }
      return acc;
    });
  };
}
export {
  duplicate
};