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diff --git a/date-fns/src/max/index.ts b/date-fns/src/max/index.ts
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+import toDate from '../toDate/index'
+import requiredArgs from '../_lib/requiredArgs/index'
+
+/**
+ * @name max
+ * @category Common Helpers
+ * @summary Return the latest of the given dates.
+ *
+ * @description
+ * Return the latest of the given dates.
+ *
+ * ### v2.0.0 breaking changes:
+ *
+ * - [Changes that are common for the whole library](https://github.com/date-fns/date-fns/blob/master/docs/upgradeGuide.md#Common-Changes).
+ *
+ * - `max` function now accepts an array of dates rather than spread arguments.
+ *
+ *   ```javascript
+ *   // Before v2.0.0
+ *   var date1 = new Date(1989, 6, 10)
+ *   var date2 = new Date(1987, 1, 11)
+ *   var maxDate = max(date1, date2)
+ *
+ *   // v2.0.0 onward:
+ *   var dates = [new Date(1989, 6, 10), new Date(1987, 1, 11)]
+ *   var maxDate = max(dates)
+ *   ```
+ *
+ * @param {Date[]|Number[]} datesArray - the dates to compare
+ * @returns {Date} the latest of the dates
+ * @throws {TypeError} 1 argument required
+ *
+ * @example
+ * // Which of these dates is the latest?
+ * var result = max([
+ *   new Date(1989, 6, 10),
+ *   new Date(1987, 1, 11),
+ *   new Date(1995, 6, 2),
+ *   new Date(1990, 0, 1)
+ * ])
+ * //=> Sun Jul 02 1995 00:00:00
+ */
+export default function max(dirtyDatesArray: Date[] | string[] | number[]): Date {
+  requiredArgs(1, arguments)
+
+  let datesArray
+  // `dirtyDatesArray` is Array, Set or Map, or object with custom `forEach` method
+  if (dirtyDatesArray && typeof dirtyDatesArray.forEach === 'function') {
+    datesArray = dirtyDatesArray
+
+    // If `dirtyDatesArray` is Array-like Object, convert to Array.
+  } else if (typeof dirtyDatesArray === 'object' && dirtyDatesArray !== null) {
+    datesArray = Array.prototype.slice.call(dirtyDatesArray)
+  } else {
+    // `dirtyDatesArray` is non-iterable, return Invalid Date
+    return new Date(NaN)
+  }
+
+  let result: Date | undefined
+  datesArray.forEach(function(dirtyDate) {
+    const currentDate = toDate(dirtyDate)
+
+    if (result === undefined || result < currentDate || isNaN(Number(currentDate))) {
+      result = currentDate
+    }
+  })
+
+  return result || new Date(NaN)
+}