40 lines
1.2 KiB
JavaScript
40 lines
1.2 KiB
JavaScript
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var binaryIndexBy = require('./binaryIndexBy'),
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identity = require('../utility/identity');
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/** Used as references for the maximum length and index of an array. */
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var MAX_ARRAY_LENGTH = 4294967295,
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HALF_MAX_ARRAY_LENGTH = MAX_ARRAY_LENGTH >>> 1;
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/**
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* Performs a binary search of `array` to determine the index at which `value`
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* should be inserted into `array` in order to maintain its sort order.
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*
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* @private
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* @param {Array} array The sorted array to inspect.
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* @param {*} value The value to evaluate.
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* @param {boolean} [retHighest] Specify returning the highest qualified index.
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* @returns {number} Returns the index at which `value` should be inserted
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* into `array`.
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*/
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function binaryIndex(array, value, retHighest) {
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var low = 0,
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high = array ? array.length : low;
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if (typeof value == 'number' && value === value && high <= HALF_MAX_ARRAY_LENGTH) {
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while (low < high) {
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var mid = (low + high) >>> 1,
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computed = array[mid];
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if ((retHighest ? (computed <= value) : (computed < value)) && computed !== null) {
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low = mid + 1;
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} else {
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high = mid;
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}
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}
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return high;
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}
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return binaryIndexBy(array, value, identity, retHighest);
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}
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module.exports = binaryIndex;
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