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