update root readme.

update bitmap nonces readme

Author: merklejerk

README.md

@@ -15,6 +15,8 @@ This repo is an ongoing collection of useful, and occasionally clever, solidity/
     - Contracts with upgradeable logic.
 - [Big Data Storage (SSTORE2)](./patterns/big-data-storage)
     - Cost efficient on-chain storage of multi-word data accessible to contracts.
+- [Bitmap Nonces](./patterns/bitmap-nonces/)
+    - Efficiently tracking the state of many operations identifiable by a unique nonce.
 - [Commit + Reveal](./patterns/commit-reveal)
     - A two-step process for performing partially obscured on-chain actions that can't be front or back runned.
 - [EIP712 Signed Messages](./patterns/eip712-signed-messages)
@@ -52,7 +54,7 @@ This repo is an ongoing collection of useful, and occasionally clever, solidity/
 - [Read-Only Delegatecall](./patterns/readonly-delegatecall)
     - Execute arbitrary delegatecalls in your contract in a read-only manner, without side-effects.
 - [Reentrancy](./patterns/reentrancy)
-    - Explaining reentrancy vulnerabilities and patterns for addressing them.
+    - Explaining reentrancy vulnerabilities and patterns for addressing them (Checks-Effects-Interactions and reentrancy guards).
 - [Separate Allowance Targets](./patterns/separate-allowance-targets/)
     - Avoid having to migrate user allowances between upgrades with a dedicated approval contract.
 - [Stack-Too-Deep Workarounds](./patterns/stack-too-deep/)

patterns/bitmap-nonces/README.md

@@ -101,10 +101,8 @@ contract TransferRelay {
 }
 ```
 
-## In the Wild
+## Final Thoughts
 
-You can find bitmap nonces being used in major protocols such as Uniswap's [Permit2](https://github.com/Uniswap/permit2/blob/cc56ad0f3439c502c246fc5cfcc3db92bb8b7219/src/SignatureTransfer.sol#L142) and 0x's [Exchange Proxy](https://github.com/0xProject/protocol/blob/e66307ba319e8c3e2a456767403298b576abc85e/contracts/zero-ex/contracts/src/features/nft_orders/ERC721OrdersFeature.sol#L662).
-
-## The Demo
-
-The full, working example can be found [here](./TransferRelay.sol) with complete tests demonstrating its usage and gas savings [here](../../test/TransferRelay.sol).
+- You can find bitmap nonces being used in major protocols such as Uniswap's [Permit2](https://github.com/Uniswap/permit2/blob/cc56ad0f3439c502c246fc5cfcc3db92bb8b7219/src/SignatureTransfer.sol#L142) and 0x's [Exchange Proxy](https://github.com/0xProject/protocol/blob/e66307ba319e8c3e2a456767403298b576abc85e/contracts/zero-ex/contracts/src/features/nft_orders/ERC721OrdersFeature.sol#L662).
+- There is no reason you couldn't track operations that have more than 2 states using bitmap nonces. You would just simply increase the number of bits in a word assigned to each operation and adjust the mapping formula accordingly.
+- The full, working example can be found [here](./TransferRelay.sol) with complete tests demonstrating its usage and gas savings [here](../../test/TransferRelay.sol).