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- import _curry3 from "./internal/_curry3.js";
- /**
- * Returns a single item by iterating through the list, successively calling
- * the iterator function and passing it an accumulator value and the current
- * value from the array, and then passing the result to the next call.
- *
- * Similar to [`reduce`](#reduce), except moves through the input list from the
- * right to the left.
- *
- * The iterator function receives two values: *(value, acc)*, while the arguments'
- * order of `reduce`'s iterator function is *(acc, value)*. `reduceRight` may use [`reduced`](#reduced)
- * to short circuit the iteration.
- *
- * Note: `R.reduceRight` does not skip deleted or unassigned indices (sparse
- * arrays), unlike the native `Array.prototype.reduceRight` method. For more details
- * on this behavior, see:
- * https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/reduceRight#Description
- *
- * Be cautious of mutating and returning the accumulator. If you reuse it across
- * invocations, it will continue to accumulate onto the same value. The general
- * recommendation is to always return a new value. If you can't do so for
- * performance reasons, then be sure to reinitialize the accumulator on each
- * invocation.
- *
- * @func
- * @memberOf R
- * @since v0.1.0
- * @category List
- * @sig ((a, b) -> b) -> b -> [a] -> b
- * @param {Function} fn The iterator function. Receives two values, the current element from the array
- * and the accumulator.
- * @param {*} acc The accumulator value.
- * @param {Array} list The list to iterate over.
- * @return {*} The final, accumulated value.
- * @see R.reduce, R.addIndex, R.reduced
- * @example
- *
- * R.reduceRight(R.subtract, 0, [1, 2, 3, 4]) // => (1 - (2 - (3 - (4 - 0)))) = -2
- * // - -2
- * // / \ / \
- * // 1 - 1 3
- * // / \ / \
- * // 2 - ==> 2 -1
- * // / \ / \
- * // 3 - 3 4
- * // / \ / \
- * // 4 0 4 0
- *
- * @symb R.reduceRight(f, a, [b, c, d]) = f(b, f(c, f(d, a)))
- */
- var reduceRight =
- /*#__PURE__*/
- _curry3(function reduceRight(fn, acc, list) {
- var idx = list.length - 1;
- while (idx >= 0) {
- acc = fn(list[idx], acc);
- if (acc && acc['@@transducer/reduced']) {
- acc = acc['@@transducer/value'];
- break;
- }
- idx -= 1;
- }
- return acc;
- });
- export default reduceRight;
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