From 1fd993bc01890bf6bd974aaf3d709bdf0a79b9bf Mon Sep 17 00:00:00 2001
From: skyge <1506186404li@gmail.com>
Date: Sat, 26 Jan 2019 00:16:40 +0800
Subject: [PATCH] Unify code comments style. (#1603)

* Updated code style to no more than120 characters per line.

* Unify code comments style with Doxygen-style tags.
---
 .../distribution/RefundableCrowdsale.sol      |  4 +--
 .../validation/WhitelistCrowdsale.sol         | 10 +++---
 contracts/drafts/SignatureBouncer.sol         |  8 ++---
 contracts/drafts/SignedSafeMath.sol           | 16 ++++-----
 contracts/drafts/TokenVesting.sol             |  6 ++--
 contracts/introspection/ERC165.sol            |  2 +-
 contracts/introspection/ERC165Checker.sol     | 10 +++---
 contracts/math/Math.sol                       | 16 ++++-----
 contracts/math/SafeMath.sol                   | 22 ++++++------
 .../ERC165/ERC165InterfacesSupported.sol      |  3 +-
 contracts/payment/PullPayment.sol             | 20 +++++------
 .../payment/escrow/ConditionalEscrow.sol      |  8 ++---
 contracts/payment/escrow/Escrow.sol           | 34 +++++++++----------
 contracts/token/ERC20/ERC20.sol               | 30 ++++++++--------
 contracts/token/ERC20/ERC20Burnable.sol       |  4 +--
 contracts/token/ERC20/ERC20Pausable.sol       |  2 +-
 contracts/token/ERC721/ERC721.sol             | 21 ++++++------
 contracts/token/ERC721/ERC721Enumerable.sol   |  4 +--
 contracts/token/ERC721/ERC721Metadata.sol     |  2 +-
 contracts/token/ERC721/ERC721Pausable.sol     |  2 +-
 contracts/token/ERC721/IERC721Receiver.sol    |  2 +-
 21 files changed, 113 insertions(+), 113 deletions(-)

diff --git a/contracts/crowdsale/distribution/RefundableCrowdsale.sol b/contracts/crowdsale/distribution/RefundableCrowdsale.sol
index f2ba9e9f7..637bc24fb 100644
--- a/contracts/crowdsale/distribution/RefundableCrowdsale.sol
+++ b/contracts/crowdsale/distribution/RefundableCrowdsale.sol
@@ -6,8 +6,8 @@ import "../../payment/escrow/RefundEscrow.sol";
 
 /**
  * @title RefundableCrowdsale
- * @dev Extension of Crowdsale contract that adds a funding goal, and the possibility of users getting a refund if goal
- * is not met.
+ * @dev Extension of Crowdsale contract that adds a funding goal, and the possibility of users getting a refund
+ * if goal is not met.
  *
  * Deprecated, use RefundablePostDeliveryCrowdsale instead. Note that if you allow tokens to be traded before the goal
  * is met, then an attack is possible in which the attacker purchases tokens from the crowdsale and when they sees that
diff --git a/contracts/crowdsale/validation/WhitelistCrowdsale.sol b/contracts/crowdsale/validation/WhitelistCrowdsale.sol
index b838bb975..9453e4702 100644
--- a/contracts/crowdsale/validation/WhitelistCrowdsale.sol
+++ b/contracts/crowdsale/validation/WhitelistCrowdsale.sol
@@ -9,11 +9,11 @@ import "../../access/roles/WhitelistedRole.sol";
  */
 contract WhitelistCrowdsale is WhitelistedRole, Crowdsale {
     /**
-    * @dev Extend parent behavior requiring beneficiary to be whitelisted. Note that no
-    * restriction is imposed on the account sending the transaction.
-    * @param _beneficiary Token beneficiary
-    * @param _weiAmount Amount of wei contributed
-    */
+     * @dev Extend parent behavior requiring beneficiary to be whitelisted. Note that no
+     * restriction is imposed on the account sending the transaction.
+     * @param _beneficiary Token beneficiary
+     * @param _weiAmount Amount of wei contributed
+     */
     function _preValidatePurchase(address _beneficiary, uint256 _weiAmount) internal view {
         require(isWhitelisted(_beneficiary));
         super._preValidatePurchase(_beneficiary, _weiAmount);
diff --git a/contracts/drafts/SignatureBouncer.sol b/contracts/drafts/SignatureBouncer.sol
index 0f259d399..89f1f17ae 100644
--- a/contracts/drafts/SignatureBouncer.sol
+++ b/contracts/drafts/SignatureBouncer.sol
@@ -92,10 +92,10 @@ contract SignatureBouncer is SignerRole {
     }
 
     /**
-        * @dev is the signature of `this + sender + methodId + params(s)` from a signer?
-        * @notice the signature parameter of the method being validated must be the "last" parameter
-        * @return bool
-        */
+     * @dev is the signature of `this + sender + methodId + params(s)` from a signer?
+     * @notice the signature parameter of the method being validated must be the "last" parameter
+     * @return bool
+     */
     function _isValidSignatureAndData(address account, bytes memory signature) internal view returns (bool) {
         require(msg.data.length > _SIGNATURE_SIZE);
 
diff --git a/contracts/drafts/SignedSafeMath.sol b/contracts/drafts/SignedSafeMath.sol
index 24b217be8..b969e1f74 100644
--- a/contracts/drafts/SignedSafeMath.sol
+++ b/contracts/drafts/SignedSafeMath.sol
@@ -8,8 +8,8 @@ library SignedSafeMath {
     int256 constant private INT256_MIN = -2**255;
 
     /**
-    * @dev Multiplies two signed integers, reverts on overflow.
-    */
+     * @dev Multiplies two signed integers, reverts on overflow.
+     */
     function mul(int256 a, int256 b) internal pure returns (int256) {
         // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
         // benefit is lost if 'b' is also tested.
@@ -27,8 +27,8 @@ library SignedSafeMath {
     }
 
     /**
-    * @dev Integer division of two signed integers truncating the quotient, reverts on division by zero.
-    */
+     * @dev Integer division of two signed integers truncating the quotient, reverts on division by zero.
+     */
     function div(int256 a, int256 b) internal pure returns (int256) {
         require(b != 0); // Solidity only automatically asserts when dividing by 0
         require(!(b == -1 && a == INT256_MIN)); // This is the only case of overflow
@@ -39,8 +39,8 @@ library SignedSafeMath {
     }
 
     /**
-    * @dev Subtracts two signed integers, reverts on overflow.
-    */
+     * @dev Subtracts two signed integers, reverts on overflow.
+     */
     function sub(int256 a, int256 b) internal pure returns (int256) {
         int256 c = a - b;
         require((b >= 0 && c <= a) || (b < 0 && c > a));
@@ -49,8 +49,8 @@ library SignedSafeMath {
     }
 
     /**
-    * @dev Adds two signed integers, reverts on overflow.
-    */
+     * @dev Adds two signed integers, reverts on overflow.
+     */
     function add(int256 a, int256 b) internal pure returns (int256) {
         int256 c = a + b;
         require((b >= 0 && c >= a) || (b < 0 && c < a));
diff --git a/contracts/drafts/TokenVesting.sol b/contracts/drafts/TokenVesting.sol
index 117dccba1..7bd4e02cf 100644
--- a/contracts/drafts/TokenVesting.sol
+++ b/contracts/drafts/TokenVesting.sol
@@ -12,9 +12,9 @@ import "../math/SafeMath.sol";
  */
 contract TokenVesting is Ownable {
     // The vesting schedule is time-based (i.e. using block timestamps as opposed to e.g. block numbers), and is
-    // therefore sensitive to timestamp manipulation (which is something miners can do, to a certain degree). Therefore,
-    // it is recommended to avoid using short time durations (less than a minute). Typical vesting schemes, with a cliff
-    // period of a year and a duration of four years, are safe to use.
+    // therefore sensitive to timestamp manipulation (which is something miners can do, to a certain degree).Therefore,
+    // it is recommended to avoid using short time durations (less than a minute). Typical vesting schemes, with a
+    // cliff period of a year and a duration of four years, are safe to use.
     // solhint-disable not-rely-on-time
 
     using SafeMath for uint256;
diff --git a/contracts/introspection/ERC165.sol b/contracts/introspection/ERC165.sol
index 540a3b525..3bc0f2db9 100644
--- a/contracts/introspection/ERC165.sol
+++ b/contracts/introspection/ERC165.sol
@@ -9,7 +9,7 @@ import "./IERC165.sol";
  */
 contract ERC165 is IERC165 {
     bytes4 private constant _INTERFACE_ID_ERC165 = 0x01ffc9a7;
-    /**
+    /*
      * 0x01ffc9a7 ===
      *     bytes4(keccak256('supportsInterface(bytes4)'))
      */
diff --git a/contracts/introspection/ERC165Checker.sol b/contracts/introspection/ERC165Checker.sol
index 0234e16ba..28b194945 100644
--- a/contracts/introspection/ERC165Checker.sol
+++ b/contracts/introspection/ERC165Checker.sol
@@ -10,7 +10,7 @@ library ERC165Checker {
     bytes4 private constant _INTERFACE_ID_INVALID = 0xffffffff;
 
     bytes4 private constant _INTERFACE_ID_ERC165 = 0x01ffc9a7;
-    /**
+    /*
      * 0x01ffc9a7 ===
      *     bytes4(keccak256('supportsInterface(bytes4)'))
      */
@@ -109,15 +109,15 @@ library ERC165Checker {
             mstore(output, 0x0)
 
             success := staticcall(
-                30000,                                 // 30k gas
-                account,                            // To addr
+                30000,                   // 30k gas
+                account,                 // To addr
                 encodedParams_data,
                 encodedParams_size,
                 output,
-                0x20                                     // Outputs are 32 bytes long
+                0x20                     // Outputs are 32 bytes long
             )
 
-            result := mload(output)    // Load the result
+            result := mload(output)      // Load the result
         }
     }
 }
diff --git a/contracts/math/Math.sol b/contracts/math/Math.sol
index 9eb3fe021..d12fa39c6 100644
--- a/contracts/math/Math.sol
+++ b/contracts/math/Math.sol
@@ -6,24 +6,24 @@ pragma solidity ^0.5.2;
  */
 library Math {
     /**
-    * @dev Returns the largest of two numbers.
-    */
+     * @dev Returns the largest of two numbers.
+     */
     function max(uint256 a, uint256 b) internal pure returns (uint256) {
         return a >= b ? a : b;
     }
 
     /**
-    * @dev Returns the smallest of two numbers.
-    */
+     * @dev Returns the smallest of two numbers.
+     */
     function min(uint256 a, uint256 b) internal pure returns (uint256) {
         return a < b ? a : b;
     }
 
     /**
-    * @dev Calculates the average of two numbers. Since these are integers,
-    * averages of an even and odd number cannot be represented, and will be
-    * rounded down.
-    */
+     * @dev Calculates the average of two numbers. Since these are integers,
+     * averages of an even and odd number cannot be represented, and will be
+     * rounded down.
+     */
     function average(uint256 a, uint256 b) internal pure returns (uint256) {
         // (a + b) / 2 can overflow, so we distribute
         return (a / 2) + (b / 2) + ((a % 2 + b % 2) / 2);
diff --git a/contracts/math/SafeMath.sol b/contracts/math/SafeMath.sol
index 759e232c6..5dd4bb903 100644
--- a/contracts/math/SafeMath.sol
+++ b/contracts/math/SafeMath.sol
@@ -6,8 +6,8 @@ pragma solidity ^0.5.2;
  */
 library SafeMath {
     /**
-    * @dev Multiplies two unsigned integers, reverts on overflow.
-    */
+     * @dev Multiplies two unsigned integers, reverts on overflow.
+     */
     function mul(uint256 a, uint256 b) internal pure returns (uint256) {
         // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
         // benefit is lost if 'b' is also tested.
@@ -23,8 +23,8 @@ library SafeMath {
     }
 
     /**
-    * @dev Integer division of two unsigned integers truncating the quotient, reverts on division by zero.
-    */
+     * @dev Integer division of two unsigned integers truncating the quotient, reverts on division by zero.
+     */
     function div(uint256 a, uint256 b) internal pure returns (uint256) {
         // Solidity only automatically asserts when dividing by 0
         require(b > 0);
@@ -35,8 +35,8 @@ library SafeMath {
     }
 
     /**
-    * @dev Subtracts two unsigned integers, reverts on overflow (i.e. if subtrahend is greater than minuend).
-    */
+     * @dev Subtracts two unsigned integers, reverts on overflow (i.e. if subtrahend is greater than minuend).
+     */
     function sub(uint256 a, uint256 b) internal pure returns (uint256) {
         require(b <= a);
         uint256 c = a - b;
@@ -45,8 +45,8 @@ library SafeMath {
     }
 
     /**
-    * @dev Adds two unsigned integers, reverts on overflow.
-    */
+     * @dev Adds two unsigned integers, reverts on overflow.
+     */
     function add(uint256 a, uint256 b) internal pure returns (uint256) {
         uint256 c = a + b;
         require(c >= a);
@@ -55,9 +55,9 @@ library SafeMath {
     }
 
     /**
-    * @dev Divides two unsigned integers and returns the remainder (unsigned integer modulo),
-    * reverts when dividing by zero.
-    */
+     * @dev Divides two unsigned integers and returns the remainder (unsigned integer modulo),
+     * reverts when dividing by zero.
+     */
     function mod(uint256 a, uint256 b) internal pure returns (uint256) {
         require(b != 0);
         return a % b;
diff --git a/contracts/mocks/ERC165/ERC165InterfacesSupported.sol b/contracts/mocks/ERC165/ERC165InterfacesSupported.sol
index 241be723f..2a5e8017b 100644
--- a/contracts/mocks/ERC165/ERC165InterfacesSupported.sol
+++ b/contracts/mocks/ERC165/ERC165InterfacesSupported.sol
@@ -4,6 +4,7 @@ import "../../introspection/IERC165.sol";
 
 /**
  * https://github.com/ethereum/EIPs/blob/master/EIPS/eip-214.md#specification
+ * From the specification:
  * > Any attempts to make state-changing operations inside an execution instance with STATIC set to true will instead
  * throw an exception.
  * > These operations include [...], LOG0, LOG1, LOG2, [...]
@@ -13,7 +14,7 @@ import "../../introspection/IERC165.sol";
  */
 contract SupportsInterfaceWithLookupMock is IERC165 {
     bytes4 public constant INTERFACE_ID_ERC165 = 0x01ffc9a7;
-    /**
+    /*
      * 0x01ffc9a7 ===
      *     bytes4(keccak256('supportsInterface(bytes4)'))
      */
diff --git a/contracts/payment/PullPayment.sol b/contracts/payment/PullPayment.sol
index ccfb12a48..0685eeb17 100644
--- a/contracts/payment/PullPayment.sol
+++ b/contracts/payment/PullPayment.sol
@@ -15,26 +15,26 @@ contract PullPayment {
     }
 
     /**
-    * @dev Withdraw accumulated balance.
-    * @param payee Whose balance will be withdrawn.
-    */
+     * @dev Withdraw accumulated balance.
+     * @param payee Whose balance will be withdrawn.
+     */
     function withdrawPayments(address payable payee) public {
         _escrow.withdraw(payee);
     }
 
     /**
-    * @dev Returns the credit owed to an address.
-    * @param dest The creditor's address.
-    */
+     * @dev Returns the credit owed to an address.
+     * @param dest The creditor's address.
+     */
     function payments(address dest) public view returns (uint256) {
         return _escrow.depositsOf(dest);
     }
 
     /**
-    * @dev Called by the payer to store the sent amount as credit to be pulled.
-    * @param dest The destination address of the funds.
-    * @param amount The amount to transfer.
-    */
+     * @dev Called by the payer to store the sent amount as credit to be pulled.
+     * @param dest The destination address of the funds.
+     * @param amount The amount to transfer.
+     */
     function _asyncTransfer(address dest, uint256 amount) internal {
         _escrow.deposit.value(amount)(dest);
     }
diff --git a/contracts/payment/escrow/ConditionalEscrow.sol b/contracts/payment/escrow/ConditionalEscrow.sol
index 425c53277..4b2213792 100644
--- a/contracts/payment/escrow/ConditionalEscrow.sol
+++ b/contracts/payment/escrow/ConditionalEscrow.sol
@@ -9,10 +9,10 @@ import "./Escrow.sol";
  */
 contract ConditionalEscrow is Escrow {
     /**
-    * @dev Returns whether an address is allowed to withdraw their funds. To be
-    * implemented by derived contracts.
-    * @param payee The destination address of the funds.
-    */
+     * @dev Returns whether an address is allowed to withdraw their funds. To be
+     * implemented by derived contracts.
+     * @param payee The destination address of the funds.
+     */
     function withdrawalAllowed(address payee) public view returns (bool);
 
     function withdraw(address payable payee) public {
diff --git a/contracts/payment/escrow/Escrow.sol b/contracts/payment/escrow/Escrow.sol
index 8497c4f91..cb7284e62 100644
--- a/contracts/payment/escrow/Escrow.sol
+++ b/contracts/payment/escrow/Escrow.sol
@@ -4,17 +4,17 @@ import "../../math/SafeMath.sol";
 import "../../ownership/Secondary.sol";
 
  /**
- * @title Escrow
- * @dev Base escrow contract, holds funds designated for a payee until they
- * withdraw them.
- * @dev Intended usage: This contract (and derived escrow contracts) should be a
- * standalone contract, that only interacts with the contract that instantiated
- * it. That way, it is guaranteed that all Ether will be handled according to
- * the Escrow rules, and there is no need to check for payable functions or
- * transfers in the inheritance tree. The contract that uses the escrow as its
- * payment method should be its primary, and provide public methods redirecting
- * to the escrow's deposit and withdraw.
- */
+  * @title Escrow
+  * @dev Base escrow contract, holds funds designated for a payee until they
+  * withdraw them.
+  * @dev Intended usage: This contract (and derived escrow contracts) should be a
+  * standalone contract, that only interacts with the contract that instantiated
+  * it. That way, it is guaranteed that all Ether will be handled according to
+  * the Escrow rules, and there is no need to check for payable functions or
+  * transfers in the inheritance tree. The contract that uses the escrow as its
+  * payment method should be its primary, and provide public methods redirecting
+  * to the escrow's deposit and withdraw.
+  */
 contract Escrow is Secondary {
     using SafeMath for uint256;
 
@@ -28,9 +28,9 @@ contract Escrow is Secondary {
     }
 
     /**
-    * @dev Stores the sent amount as credit to be withdrawn.
-    * @param payee The destination address of the funds.
-    */
+     * @dev Stores the sent amount as credit to be withdrawn.
+     * @param payee The destination address of the funds.
+     */
     function deposit(address payee) public onlyPrimary payable {
         uint256 amount = msg.value;
         _deposits[payee] = _deposits[payee].add(amount);
@@ -39,9 +39,9 @@ contract Escrow is Secondary {
     }
 
     /**
-    * @dev Withdraw accumulated balance for a payee.
-    * @param payee The address whose funds will be withdrawn and transferred to.
-    */
+     * @dev Withdraw accumulated balance for a payee.
+     * @param payee The address whose funds will be withdrawn and transferred to.
+     */
     function withdraw(address payable payee) public onlyPrimary {
         uint256 payment = _deposits[payee];
 
diff --git a/contracts/token/ERC20/ERC20.sol b/contracts/token/ERC20/ERC20.sol
index 519271ff5..b60cc11ad 100644
--- a/contracts/token/ERC20/ERC20.sol
+++ b/contracts/token/ERC20/ERC20.sol
@@ -25,17 +25,17 @@ contract ERC20 is IERC20 {
     uint256 private _totalSupply;
 
     /**
-    * @dev Total number of tokens in existence
-    */
+     * @dev Total number of tokens in existence
+     */
     function totalSupply() public view returns (uint256) {
         return _totalSupply;
     }
 
     /**
-    * @dev Gets the balance of the specified address.
-    * @param owner The address to query the balance of.
-    * @return An uint256 representing the amount owned by the passed address.
-    */
+     * @dev Gets the balance of the specified address.
+     * @param owner The address to query the balance of.
+     * @return An uint256 representing the amount owned by the passed address.
+     */
     function balanceOf(address owner) public view returns (uint256) {
         return _balances[owner];
     }
@@ -51,10 +51,10 @@ contract ERC20 is IERC20 {
     }
 
     /**
-    * @dev Transfer token for a specified address
-    * @param to The address to transfer to.
-    * @param value The amount to be transferred.
-    */
+     * @dev Transfer token for a specified address
+     * @param to The address to transfer to.
+     * @param value The amount to be transferred.
+     */
     function transfer(address to, uint256 value) public returns (bool) {
         _transfer(msg.sender, to, value);
         return true;
@@ -119,11 +119,11 @@ contract ERC20 is IERC20 {
     }
 
     /**
-    * @dev Transfer token for a specified addresses
-    * @param from The address to transfer from.
-    * @param to The address to transfer to.
-    * @param value The amount to be transferred.
-    */
+     * @dev Transfer token for a specified addresses
+     * @param from The address to transfer from.
+     * @param to The address to transfer to.
+     * @param value The amount to be transferred.
+     */
     function _transfer(address from, address to, uint256 value) internal {
         require(to != address(0));
 
diff --git a/contracts/token/ERC20/ERC20Burnable.sol b/contracts/token/ERC20/ERC20Burnable.sol
index c43a5addb..91f67fa4a 100644
--- a/contracts/token/ERC20/ERC20Burnable.sol
+++ b/contracts/token/ERC20/ERC20Burnable.sol
@@ -17,8 +17,8 @@ contract ERC20Burnable is ERC20 {
 
     /**
      * @dev Burns a specific amount of tokens from the target address and decrements allowance
-     * @param from address The address which you want to send tokens from
-     * @param value uint256 The amount of token to be burned
+     * @param from address The account whose tokens will be burned.
+     * @param value uint256 The amount of token to be burned.
      */
     function burnFrom(address from, uint256 value) public {
         _burnFrom(from, value);
diff --git a/contracts/token/ERC20/ERC20Pausable.sol b/contracts/token/ERC20/ERC20Pausable.sol
index 9f68fb0fa..05dfb4ab7 100644
--- a/contracts/token/ERC20/ERC20Pausable.sol
+++ b/contracts/token/ERC20/ERC20Pausable.sol
@@ -6,7 +6,7 @@ import "../../lifecycle/Pausable.sol";
 /**
  * @title Pausable token
  * @dev ERC20 modified with pausable transfers.
- **/
+ */
 contract ERC20Pausable is ERC20, Pausable {
     function transfer(address to, uint256 value) public whenNotPaused returns (bool) {
         return super.transfer(to, value);
diff --git a/contracts/token/ERC721/ERC721.sol b/contracts/token/ERC721/ERC721.sol
index d26ce72e5..d844a5e73 100644
--- a/contracts/token/ERC721/ERC721.sol
+++ b/contracts/token/ERC721/ERC721.sol
@@ -64,7 +64,7 @@ contract ERC721 is ERC165, IERC721 {
     /**
      * @dev Gets the owner of the specified token ID
      * @param tokenId uint256 ID of the token to query the owner of
-     * @return owner address currently marked as the owner of the given token ID
+     * @return address currently marked as the owner of the given token ID
      */
     function ownerOf(uint256 tokenId) public view returns (address) {
         address owner = _tokenOwner[tokenId];
@@ -125,11 +125,11 @@ contract ERC721 is ERC165, IERC721 {
     /**
      * @dev Transfers the ownership of a given token ID to another address
      * Usage of this method is discouraged, use `safeTransferFrom` whenever possible
-     * Requires the msg sender to be the owner, approved, or operator
+     * Requires the msg.sender to be the owner, approved, or operator
      * @param from current owner of the token
      * @param to address to receive the ownership of the given token ID
      * @param tokenId uint256 ID of the token to be transferred
-    */
+     */
     function transferFrom(address from, address to, uint256 tokenId) public {
         require(_isApprovedOrOwner(msg.sender, tokenId));
 
@@ -142,12 +142,11 @@ contract ERC721 is ERC165, IERC721 {
      * which is called upon a safe transfer, and return the magic value
      * `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`; otherwise,
      * the transfer is reverted.
-     *
-     * Requires the msg sender to be the owner, approved, or operator
+     * Requires the msg.sender to be the owner, approved, or operator
      * @param from current owner of the token
      * @param to address to receive the ownership of the given token ID
      * @param tokenId uint256 ID of the token to be transferred
-    */
+     */
     function safeTransferFrom(address from, address to, uint256 tokenId) public {
         safeTransferFrom(from, to, tokenId, "");
     }
@@ -158,7 +157,7 @@ contract ERC721 is ERC165, IERC721 {
      * which is called upon a safe transfer, and return the magic value
      * `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`; otherwise,
      * the transfer is reverted.
-     * Requires the msg sender to be the owner, approved, or operator
+     * Requires the msg.sender to be the owner, approved, or operator
      * @param from current owner of the token
      * @param to address to receive the ownership of the given token ID
      * @param tokenId uint256 ID of the token to be transferred
@@ -172,7 +171,7 @@ contract ERC721 is ERC165, IERC721 {
     /**
      * @dev Returns whether the specified token exists
      * @param tokenId uint256 ID of the token to query the existence of
-     * @return whether the token exists
+     * @return bool whether the token exists
      */
     function _exists(uint256 tokenId) internal view returns (bool) {
         address owner = _tokenOwner[tokenId];
@@ -184,7 +183,7 @@ contract ERC721 is ERC165, IERC721 {
      * @param spender address of the spender to query
      * @param tokenId uint256 ID of the token to be transferred
      * @return bool whether the msg.sender is approved for the given token ID,
-     *    is an operator of the owner, or is the owner of the token
+     * is an operator of the owner, or is the owner of the token
      */
     function _isApprovedOrOwner(address spender, uint256 tokenId) internal view returns (bool) {
         address owner = ownerOf(tokenId);
@@ -240,7 +239,7 @@ contract ERC721 is ERC165, IERC721 {
      * @param from current owner of the token
      * @param to address to receive the ownership of the given token ID
      * @param tokenId uint256 ID of the token to be transferred
-    */
+     */
     function _transferFrom(address from, address to, uint256 tokenId) internal {
         require(ownerOf(tokenId) == from);
         require(to != address(0));
@@ -262,7 +261,7 @@ contract ERC721 is ERC165, IERC721 {
      * @param to target address that will receive the tokens
      * @param tokenId uint256 ID of the token to be transferred
      * @param _data bytes optional data to send along with the call
-     * @return whether the call correctly returned the expected magic value
+     * @return bool whether the call correctly returned the expected magic value
      */
     function _checkOnERC721Received(address from, address to, uint256 tokenId, bytes memory _data)
         internal returns (bool)
diff --git a/contracts/token/ERC721/ERC721Enumerable.sol b/contracts/token/ERC721/ERC721Enumerable.sol
index 205395d0e..171bf8ac6 100644
--- a/contracts/token/ERC721/ERC721Enumerable.sol
+++ b/contracts/token/ERC721/ERC721Enumerable.sol
@@ -22,7 +22,7 @@ contract ERC721Enumerable is ERC165, ERC721, IERC721Enumerable {
     mapping(uint256 => uint256) private _allTokensIndex;
 
     bytes4 private constant _INTERFACE_ID_ERC721_ENUMERABLE = 0x780e9d63;
-    /**
+    /*
      * 0x780e9d63 ===
      *     bytes4(keccak256('totalSupply()')) ^
      *     bytes4(keccak256('tokenOfOwnerByIndex(address,uint256)')) ^
@@ -73,7 +73,7 @@ contract ERC721Enumerable is ERC165, ERC721, IERC721Enumerable {
      * @param from current owner of the token
      * @param to address to receive the ownership of the given token ID
      * @param tokenId uint256 ID of the token to be transferred
-    */
+     */
     function _transferFrom(address from, address to, uint256 tokenId) internal {
         super._transferFrom(from, to, tokenId);
 
diff --git a/contracts/token/ERC721/ERC721Metadata.sol b/contracts/token/ERC721/ERC721Metadata.sol
index 6615aad05..0da71d0bf 100644
--- a/contracts/token/ERC721/ERC721Metadata.sol
+++ b/contracts/token/ERC721/ERC721Metadata.sol
@@ -15,7 +15,7 @@ contract ERC721Metadata is ERC165, ERC721, IERC721Metadata {
     mapping(uint256 => string) private _tokenURIs;
 
     bytes4 private constant _INTERFACE_ID_ERC721_METADATA = 0x5b5e139f;
-    /**
+    /*
      * 0x5b5e139f ===
      *     bytes4(keccak256('name()')) ^
      *     bytes4(keccak256('symbol()')) ^
diff --git a/contracts/token/ERC721/ERC721Pausable.sol b/contracts/token/ERC721/ERC721Pausable.sol
index 00a945081..5143a3775 100644
--- a/contracts/token/ERC721/ERC721Pausable.sol
+++ b/contracts/token/ERC721/ERC721Pausable.sol
@@ -6,7 +6,7 @@ import "../../lifecycle/Pausable.sol";
 /**
  * @title ERC721 Non-Fungible Pausable token
  * @dev ERC721 modified with pausable transfers.
- **/
+ */
 contract ERC721Pausable is ERC721, Pausable {
     function approve(address to, uint256 tokenId) public whenNotPaused {
         super.approve(to, tokenId);
diff --git a/contracts/token/ERC721/IERC721Receiver.sol b/contracts/token/ERC721/IERC721Receiver.sol
index 50b8b6942..bd76e674c 100644
--- a/contracts/token/ERC721/IERC721Receiver.sol
+++ b/contracts/token/ERC721/IERC721Receiver.sol
@@ -18,7 +18,7 @@ contract IERC721Receiver {
      * @param from The address which previously owned the token
      * @param tokenId The NFT identifier which is being transferred
      * @param data Additional data with no specified format
-     * @return `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`
+     * @return bytes4 `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`
      */
     function onERC721Received(address operator, address from, uint256 tokenId, bytes memory data)
     public returns (bytes4);