--- /dev/null
+/** Used as the internal argument placeholder. */
+var PLACEHOLDER = '__lodash_placeholder__';
+
+/**
+ * Replaces all `placeholder` elements in `array` with an internal placeholder
+ * and returns an array of their indexes.
+ *
+ * @private
+ * @param {Array} array The array to modify.
+ * @param {*} placeholder The placeholder to replace.
+ * @returns {Array} Returns the new array of placeholder indexes.
+ */
+function replaceHolders(array, placeholder) {
+ var index = -1,
+ length = array.length,
+ resIndex = 0,
+ result = [];
+
+ while (++index < length) {
+ var value = array[index];
+ if (value === placeholder || value === PLACEHOLDER) {
+ array[index] = PLACEHOLDER;
+ result[resIndex++] = index;
+ }
+ }
+ return result;
+}
+
+module.exports = replaceHolders;