1 | var _curry2 =
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2 | /*#__PURE__*/
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3 | require("./internal/_curry2");
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4 | /**
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5 | * Builds a list from a seed value. Accepts an iterator function, which returns
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6 | * either false to stop iteration or an array of length 2 containing the value
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7 | * to add to the resulting list and the seed to be used in the next call to the
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8 | * iterator function.
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9 | *
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10 | * The iterator function receives one argument: *(seed)*.
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11 | *
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12 | * @func
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13 | * @memberOf R
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14 | * @since v0.10.0
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15 | * @category List
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16 | * @sig (a -> [b]) -> * -> [b]
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17 | * @param {Function} fn The iterator function. receives one argument, `seed`, and returns
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18 | * either false to quit iteration or an array of length two to proceed. The element
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19 | * at index 0 of this array will be added to the resulting array, and the element
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20 | * at index 1 will be passed to the next call to `fn`.
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21 | * @param {*} seed The seed value.
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22 | * @return {Array} The final list.
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23 | * @example
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24 | *
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25 | * const f = n => n > 50 ? false : [-n, n + 10];
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26 | * R.unfold(f, 10); //=> [-10, -20, -30, -40, -50]
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27 | * @symb R.unfold(f, x) = [f(x)[0], f(f(x)[1])[0], f(f(f(x)[1])[1])[0], ...]
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28 | */
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29 |
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30 |
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31 | var unfold =
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32 | /*#__PURE__*/
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33 | _curry2(function unfold(fn, seed) {
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34 | var pair = fn(seed);
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35 | var result = [];
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36 |
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37 | while (pair && pair.length) {
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38 | result[result.length] = pair[0];
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39 | pair = fn(pair[1]);
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40 | }
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41 |
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42 | return result;
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43 | });
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44 |
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45 | module.exports = unfold; |
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