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- import _curry3 from "./internal/_curry3.js";
- import _xReduce from "./internal/_xReduce.js";
- import _xwrap from "./internal/_xwrap.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.
- *
- * The iterator function receives two values: *(acc, value)*. It may use
- * [`R.reduced`](#reduced) to shortcut the iteration.
- *
- * The arguments' order of [`reduceRight`](#reduceRight)'s iterator function
- * is *(value, acc)*.
- *
- * Note: `R.reduce` does not skip deleted or unassigned indices (sparse
- * arrays), unlike the native `Array.prototype.reduce` method. For more details
- * on this behavior, see:
- * https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/reduce#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.
- *
- * Dispatches to the `reduce` method of the third argument, if present. When
- * doing so, it is up to the user to handle the [`R.reduced`](#reduced)
- * shortcuting, as this is not implemented by `reduce`.
- *
- * @func
- * @memberOf R
- * @since v0.1.0
- * @category List
- * @sig ((a, b) -> a) -> a -> [b] -> a
- * @param {Function} fn The iterator function. Receives two values, the accumulator and the
- * current element from the array.
- * @param {*} acc The accumulator value.
- * @param {Array} list The list to iterate over.
- * @return {*} The final, accumulated value.
- * @see R.reduced, R.addIndex, R.reduceRight
- * @example
- *
- * R.reduce(R.subtract, 0, [1, 2, 3, 4]) // => ((((0 - 1) - 2) - 3) - 4) = -10
- * // - -10
- * // / \ / \
- * // - 4 -6 4
- * // / \ / \
- * // - 3 ==> -3 3
- * // / \ / \
- * // - 2 -1 2
- * // / \ / \
- * // 0 1 0 1
- *
- * @symb R.reduce(f, a, [b, c, d]) = f(f(f(a, b), c), d)
- */
- var reduce =
- /*#__PURE__*/
- _curry3(function (xf, acc, list) {
- return _xReduce(typeof xf === 'function' ? _xwrap(xf) : xf, acc, list);
- });
- export default reduce;
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