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