1 | import _curry2 from "./internal/_curry2.js";
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2 | import _dispatchable from "./internal/_dispatchable.js";
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3 | import _xtakeWhile from "./internal/_xtakeWhile.js";
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4 | import slice from "./slice.js";
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5 | /**
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6 | * Returns a new list containing the first `n` elements of a given list,
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7 | * passing each value to the supplied predicate function, and terminating when
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8 | * the predicate function returns `false`. Excludes the element that caused the
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9 | * predicate function to fail. The predicate function is passed one argument:
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10 | * *(value)*.
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11 | *
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12 | * Dispatches to the `takeWhile` method of the second argument, if present.
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13 | *
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14 | * Acts as a transducer if a transformer is given in list position.
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15 | *
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16 | * @func
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17 | * @memberOf R
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18 | * @since v0.1.0
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19 | * @category List
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20 | * @sig (a -> Boolean) -> [a] -> [a]
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21 | * @sig (a -> Boolean) -> String -> String
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22 | * @param {Function} fn The function called per iteration.
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23 | * @param {Array} xs The collection to iterate over.
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24 | * @return {Array} A new array.
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25 | * @see R.dropWhile, R.transduce, R.addIndex
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26 | * @example
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27 | *
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28 | * const isNotFour = x => x !== 4;
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29 | *
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30 | * R.takeWhile(isNotFour, [1, 2, 3, 4, 3, 2, 1]); //=> [1, 2, 3]
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31 | *
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32 | * R.takeWhile(x => x !== 'd' , 'Ramda'); //=> 'Ram'
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33 | */
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34 |
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35 | var takeWhile =
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36 | /*#__PURE__*/
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37 | _curry2(
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38 | /*#__PURE__*/
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39 | _dispatchable(['takeWhile'], _xtakeWhile, function takeWhile(fn, xs) {
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40 | var idx = 0;
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41 | var len = xs.length;
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42 |
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43 | while (idx < len && fn(xs[idx])) {
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44 | idx += 1;
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45 | }
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46 |
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47 | return slice(0, idx, xs);
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48 | }));
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49 |
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50 | export default takeWhile; |
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