--- /dev/null
+/**
+ * Performs a [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero)
+ * comparison between two values to determine if they are equivalent.
+ *
+ * @static
+ * @memberOf _
+ * @category Lang
+ * @param {*} value The value to compare.
+ * @param {*} other The other value to compare.
+ * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
+ * @example
+ *
+ * var object = { 'user': 'fred' };
+ * var other = { 'user': 'fred' };
+ *
+ * _.eq(object, object);
+ * // => true
+ *
+ * _.eq(object, other);
+ * // => false
+ *
+ * _.eq('a', 'a');
+ * // => true
+ *
+ * _.eq('a', Object('a'));
+ * // => false
+ *
+ * _.eq(NaN, NaN);
+ * // => true
+ */
+function eq(value, other) {
+ return value === other || (value !== value && other !== other);
+}
+
+module.exports = eq;