From 9fdc91758dbd958a28a238a87c71b21e501a47c7 Mon Sep 17 00:00:00 2001
From: Francisco Giordano <frangio.1@gmail.com>
Date: Fri, 16 Aug 2019 20:06:35 +0200
Subject: [PATCH] add note in api ref about unreleased features

---
 contracts/math/SafeMath.sol | 9 +++++++++
 contracts/utils/Address.sol | 3 +++
 2 files changed, 12 insertions(+)

diff --git a/contracts/math/SafeMath.sol b/contracts/math/SafeMath.sol
index 5cb05fafd..2485da9cc 100644
--- a/contracts/math/SafeMath.sol
+++ b/contracts/math/SafeMath.sol
@@ -51,6 +51,9 @@ library SafeMath {
      *
      * Requirements:
      * - Subtraction cannot overflow.
+     *
+     * NOTE: This is a feature of the next version of OpenZeppelin Contracts.
+     * @dev Get it via `npm install @openzeppelin/contracts@next`.
      */
     function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
         require(b <= a, errorMessage);
@@ -107,6 +110,9 @@ library SafeMath {
      *
      * Requirements:
      * - The divisor cannot be zero.
+
+     * NOTE: This is a feature of the next version of OpenZeppelin Contracts.
+     * @dev Get it via `npm install @openzeppelin/contracts@next`.
      */
     function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
         // Solidity only automatically asserts when dividing by 0
@@ -142,6 +148,9 @@ library SafeMath {
      *
      * Requirements:
      * - The divisor cannot be zero.
+     *
+     * NOTE: This is a feature of the next version of OpenZeppelin Contracts.
+     * @dev Get it via `npm install @openzeppelin/contracts@next`.
      */
     function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
         require(b != 0, errorMessage);
diff --git a/contracts/utils/Address.sol b/contracts/utils/Address.sol
index 3ee289123..c6fa470e8 100644
--- a/contracts/utils/Address.sol
+++ b/contracts/utils/Address.sol
@@ -33,6 +33,9 @@ library Address {
     /**
      * @dev Converts an `address` into `address payable`. Note that this is
      * simply a type cast: the actual underlying value is not changed.
+     *
+     * NOTE: This is a feature of the next version of OpenZeppelin Contracts.
+     * @dev Get it via `npm install @openzeppelin/contracts@next`.
      */
     function toPayable(address account) internal pure returns (address payable) {
         return address(uint160(account));