37 lines
1.0 KiB
JavaScript
37 lines
1.0 KiB
JavaScript
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import _curry2 from "./internal/_curry2.js";
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/**
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* Takes a list and a predicate and returns a pair of lists with the following properties:
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*
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* - the result of concatenating the two output lists is equivalent to the input list;
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* - none of the elements of the first output list satisfies the predicate; and
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* - if the second output list is non-empty, its first element satisfies the predicate.
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*
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* @func
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* @memberOf R
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* @since v0.19.0
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* @category List
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* @sig (a -> Boolean) -> [a] -> [[a], [a]]
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* @param {Function} pred The predicate that determines where the array is split.
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* @param {Array} list The array to be split.
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* @return {Array}
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* @example
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*
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* R.splitWhen(R.equals(2), [1, 2, 3, 1, 2, 3]); //=> [[1], [2, 3, 1, 2, 3]]
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*/
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var splitWhen =
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/*#__PURE__*/
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_curry2(function splitWhen(pred, list) {
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var idx = 0;
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var len = list.length;
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var prefix = [];
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while (idx < len && !pred(list[idx])) {
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prefix.push(list[idx]);
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idx += 1;
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}
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return [prefix, Array.prototype.slice.call(list, idx)];
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});
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export default splitWhen;
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