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reduce.js
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reduce.js
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var _curry3 = require('./internal/_curry3');
var _reduce = require('./internal/_reduce');
/**
* 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` to shortcut the iteration.
*
* The arguments' order of `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
*
* Dispatches to the `reduce` method of the third argument, if present.
*
* @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)
*/
module.exports = _curry3(_reduce);