> For the complete documentation index, see [llms.txt](https://developers.polymath.network/polymath/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers.polymath.network/polymath/api/tokenlib.md).

# TokenLib.sol

View Source: [contracts/libraries/TokenLib.sol](https://github.com/PolymathNetwork/polymath-core/tree/096ba240a927c98e1f1a182d2efee7c4c4c1dfc5/contracts/libraries/TokenLib.sol)

**TokenLib**

## Structs

### EIP712Domain

```javascript
struct EIP712Domain {
 string name,
 uint256 chainId,
 address verifyingContract
}
```

### Acknowledgment

```javascript
struct Acknowledgment {
 string text
}
```

## Contract Members

**Constants & Variables**

```javascript
bytes32 internal constant EIP712DOMAIN_TYPEHASH;
bytes32 internal constant ACK_TYPEHASH;
bytes32 internal constant WHITELIST;
bytes32 internal constant INVESTORSKEY;
```

**Events**

```javascript
event ModuleUpgraded(uint8[]  _types, address  _module);
event ModuleArchived(uint8[]  _types, address  _module);
event ModuleUnarchived(uint8[]  _types, address  _module);
event ModuleRemoved(uint8[]  _types, address  _module);
event ModuleBudgetChanged(uint8[]  _moduleTypes, address  _module, uint256  _oldBudget, uint256  _budget);
event DocumentUpdated(bytes32 indexed _name, string  _uri, bytes32  _documentHash);
event DocumentRemoved(bytes32 indexed _name, string  _uri, bytes32  _documentHash);
```

## Functions

* [hash(struct TokenLib.EIP712Domain \_eip712Domain)](/polymath/api/tokenlib.md#hash)
* [hash(struct TokenLib.Acknowledgment \_ack)](/polymath/api/tokenlib.md#hash)
* [recoverFreezeIssuanceAckSigner(bytes \_signature)](/polymath/api/tokenlib.md#recoverfreezeissuanceacksigner)
* [recoverDisableControllerAckSigner(bytes \_signature)](/polymath/api/tokenlib.md#recoverdisablecontrolleracksigner)
* [extractSigner(struct TokenLib.Acknowledgment \_ack, bytes \_signature)](/polymath/api/tokenlib.md#extractsigner)
* [archiveModule(struct SecurityTokenStorage.ModuleData \_moduleData)](/polymath/api/tokenlib.md#archivemodule)
* [unarchiveModule(IModuleRegistry \_moduleRegistry, struct SecurityTokenStorage.ModuleData \_moduleData)](/polymath/api/tokenlib.md#unarchivemodule)
* [upgradeModule(IModuleRegistry \_moduleRegistry, struct SecurityTokenStorage.ModuleData \_moduleData)](/polymath/api/tokenlib.md#upgrademodule)
* [removeModule(address \_module, mapping(uint8 => address\[\]) \_modules, mapping(address => struct SecurityTokenStorage.ModuleData) \_modulesToData, mapping(bytes32 => address\[\]) \_names)](/polymath/api/tokenlib.md#removemodule)
* [\_removeModuleWithIndex(uint8 \_type, uint256 \_index, mapping(uint8 => address\[\]) \_modules, mapping(address => struct SecurityTokenStorage.ModuleData) \_modulesToData)](/polymath/api/tokenlib.md#_removemodulewithindex)
* [changeModuleBudget(address \_module, uint256 \_change, bool \_increase, IERC20 \_polyToken, mapping(address => struct SecurityTokenStorage.ModuleData) \_modulesToData)](/polymath/api/tokenlib.md#changemodulebudget)
* [getValueAt(struct SecurityTokenStorage.Checkpoint\[\] \_checkpoints, uint256 \_checkpointId, uint256 \_currentValue)](/polymath/api/tokenlib.md#getvalueat)
* [adjustCheckpoints(struct SecurityTokenStorage.Checkpoint\[\] \_checkpoints, uint256 \_newValue, uint256 \_currentCheckpointId)](/polymath/api/tokenlib.md#adjustcheckpoints)
* [adjustInvestorCount(uint256 \_holderCount, address \_from, address \_to, uint256 \_value, uint256 \_balanceTo, uint256 \_balanceFrom, IDataStore \_dataStore)](/polymath/api/tokenlib.md#adjustinvestorcount)
* [setDocument(mapping(bytes32 => struct SecurityTokenStorage.Document) document, bytes32\[\] docNames, mapping(bytes32 => uint256) docIndexes, bytes32 name, string uri, bytes32 documentHash)](/polymath/api/tokenlib.md#setdocument)
* [removeDocument(mapping(bytes32 => struct SecurityTokenStorage.Document) document, bytes32\[\] docNames, mapping(bytes32 => uint256) docIndexes, bytes32 name)](/polymath/api/tokenlib.md#removedocument)
* [verifyTransfer(address\[\] modules, mapping(address => struct SecurityTokenStorage.ModuleData) modulesToData, address from, address to, uint256 value, bytes data, bool transfersFrozen)](/polymath/api/tokenlib.md#verifytransfer)
* [canTransfer(bool success, bytes32 appCode, address to, uint256 value, uint256 balanceOfFrom)](/polymath/api/tokenlib.md#cantransfer)
* [\_getKey(bytes32 \_key1, address \_key2)](/polymath/api/tokenlib.md#_getkey)
* [\_isExistingInvestor(address \_investor, IDataStore dataStore)](/polymath/api/tokenlib.md#_isexistinginvestor)

### hash

```javascript
function hash(struct TokenLib.EIP712Domain _eip712Domain) internal pure
returns(bytes32)
```

**Arguments**

| Name           | Type                         | Description |
| -------------- | ---------------------------- | ----------- |
| \_eip712Domain | struct TokenLib.EIP712Domain |             |

### hash

```javascript
function hash(struct TokenLib.Acknowledgment _ack) internal pure
returns(bytes32)
```

**Arguments**

| Name  | Type                           | Description |
| ----- | ------------------------------ | ----------- |
| \_ack | struct TokenLib.Acknowledgment |             |

### recoverFreezeIssuanceAckSigner

```javascript
function recoverFreezeIssuanceAckSigner(bytes _signature) external view
returns(address)
```

**Arguments**

| Name        | Type  | Description |
| ----------- | ----- | ----------- |
| \_signature | bytes |             |

### recoverDisableControllerAckSigner

```javascript
function recoverDisableControllerAckSigner(bytes _signature) external view
returns(address)
```

**Arguments**

| Name        | Type  | Description |
| ----------- | ----- | ----------- |
| \_signature | bytes |             |

### extractSigner

```javascript
function extractSigner(struct TokenLib.Acknowledgment _ack, bytes _signature) internal view
returns(address)
```

**Arguments**

| Name        | Type                           | Description |
| ----------- | ------------------------------ | ----------- |
| \_ack       | struct TokenLib.Acknowledgment |             |
| \_signature | bytes                          |             |

### archiveModule

Archives a module attached to the SecurityToken

```javascript
function archiveModule(struct SecurityTokenStorage.ModuleData _moduleData) external nonpayable
```

**Arguments**

| Name         | Type                                   | Description  |
| ------------ | -------------------------------------- | ------------ |
| \_moduleData | struct SecurityTokenStorage.ModuleData | Storage data |

### unarchiveModule

Unarchives a module attached to the SecurityToken

```javascript
function unarchiveModule(IModuleRegistry _moduleRegistry, struct SecurityTokenStorage.ModuleData _moduleData) external nonpayable
```

**Arguments**

| Name             | Type                                   | Description  |
| ---------------- | -------------------------------------- | ------------ |
| \_moduleRegistry | IModuleRegistry                        |              |
| \_moduleData     | struct SecurityTokenStorage.ModuleData | Storage data |

### upgradeModule

Upgrades a module attached to the SecurityToken

```javascript
function upgradeModule(IModuleRegistry _moduleRegistry, struct SecurityTokenStorage.ModuleData _moduleData) external nonpayable
```

**Arguments**

| Name             | Type                                   | Description  |
| ---------------- | -------------------------------------- | ------------ |
| \_moduleRegistry | IModuleRegistry                        |              |
| \_moduleData     | struct SecurityTokenStorage.ModuleData | Storage data |

### removeModule

Removes a module attached to the SecurityToken

```javascript
function removeModule(address _module, mapping(uint8 => address[]) _modules, mapping(address => struct SecurityTokenStorage.ModuleData) _modulesToData, mapping(bytes32 => address[]) _names) external nonpayable
```

**Arguments**

| Name            | Type                                                       | Description                    |
| --------------- | ---------------------------------------------------------- | ------------------------------ |
| \_module        | address                                                    | address of module to unarchive |
| \_modules       | mapping(uint8 => address\[])                               |                                |
| \_modulesToData | mapping(address => struct SecurityTokenStorage.ModuleData) |                                |
| \_names         | mapping(bytes32 => address\[])                             |                                |

### \_removeModuleWithIndex

Internal - Removes a module attached to the SecurityToken by index

```javascript
function _removeModuleWithIndex(uint8 _type, uint256 _index, mapping(uint8 => address[]) _modules, mapping(address => struct SecurityTokenStorage.ModuleData) _modulesToData) internal nonpayable
```

**Arguments**

| Name            | Type                                                       | Description |
| --------------- | ---------------------------------------------------------- | ----------- |
| \_type          | uint8                                                      |             |
| \_index         | uint256                                                    |             |
| \_modules       | mapping(uint8 => address\[])                               |             |
| \_modulesToData | mapping(address => struct SecurityTokenStorage.ModuleData) |             |

### changeModuleBudget

allows owner to increase/decrease POLY approval of one of the modules

```javascript
function changeModuleBudget(address _module, uint256 _change, bool _increase, IERC20 _polyToken, mapping(address => struct SecurityTokenStorage.ModuleData) _modulesToData) external nonpayable
```

**Arguments**

| Name            | Type                                                       | Description                                           |
| --------------- | ---------------------------------------------------------- | ----------------------------------------------------- |
| \_module        | address                                                    | module address                                        |
| \_change        | uint256                                                    | change in allowance                                   |
| \_increase      | bool                                                       | true if budget has to be increased, false if decrease |
| \_polyToken     | IERC20                                                     |                                                       |
| \_modulesToData | mapping(address => struct SecurityTokenStorage.ModuleData) |                                                       |

### getValueAt

Queries a value at a defined checkpoint

```javascript
function getValueAt(struct SecurityTokenStorage.Checkpoint[] _checkpoints, uint256 _checkpointId, uint256 _currentValue) external view
returns(uint256)
```

**Returns**

uint256

**Arguments**

| Name           | Type                                      | Description                        |
| -------------- | ----------------------------------------- | ---------------------------------- |
| \_checkpoints  | struct SecurityTokenStorage.Checkpoint\[] | is array of Checkpoint objects     |
| \_checkpointId | uint256                                   | is the Checkpoint ID to query      |
| \_currentValue | uint256                                   | is the Current value of checkpoint |

### adjustCheckpoints

Stores the changes to the checkpoint objects

```javascript
function adjustCheckpoints(struct SecurityTokenStorage.Checkpoint[] _checkpoints, uint256 _newValue, uint256 _currentCheckpointId) external nonpayable
```

**Arguments**

| Name                  | Type                                      | Description                              |
| --------------------- | ----------------------------------------- | ---------------------------------------- |
| \_checkpoints         | struct SecurityTokenStorage.Checkpoint\[] | is the affected checkpoint object array  |
| \_newValue            | uint256                                   | is the new value that needs to be stored |
| \_currentCheckpointId | uint256                                   |                                          |

### adjustInvestorCount

Keeps track of the number of non-zero token holders

```javascript
function adjustInvestorCount(uint256 _holderCount, address _from, address _to, uint256 _value, uint256 _balanceTo, uint256 _balanceFrom, IDataStore _dataStore) external nonpayable
returns(uint256)
```

**Arguments**

| Name          | Type       | Description                     |
| ------------- | ---------- | ------------------------------- |
| \_holderCount | uint256    | Number of current token holders |
| \_from        | address    | Sender of transfer              |
| \_to          | address    | Receiver of transfer            |
| \_value       | uint256    | Value of transfer               |
| \_balanceTo   | uint256    | Balance of the \_to address     |
| \_balanceFrom | uint256    | Balance of the \_from address   |
| \_dataStore   | IDataStore | address of data store           |

### setDocument

Used to attach a new document to the contract, or update the URI or hash of an existing attached document

```javascript
function setDocument(mapping(bytes32 => struct SecurityTokenStorage.Document) document, bytes32[] docNames, mapping(bytes32 => uint256) docIndexes, bytes32 name, string uri, bytes32 documentHash) external nonpayable
```

**Arguments**

| Name         | Type                                                     | Description                                                                              |
| ------------ | -------------------------------------------------------- | ---------------------------------------------------------------------------------------- |
| document     | mapping(bytes32 => struct SecurityTokenStorage.Document) | Hash hash (of the contents) of the document.                                             |
| docNames     | bytes32\[]                                               |                                                                                          |
| docIndexes   | mapping(bytes32 => uint256)                              |                                                                                          |
| name         | bytes32                                                  | Name of the document. It should be unique always                                         |
| uri          | string                                                   | Off-chain uri of the document from where it is accessible to investors/advisors to read. |
| documentHash | bytes32                                                  | hash (of the contents) of the document.                                                  |

### removeDocument

Used to remove an existing document from the contract by giving the name of the document.

```javascript
function removeDocument(mapping(bytes32 => struct SecurityTokenStorage.Document) document, bytes32[] docNames, mapping(bytes32 => uint256) docIndexes, bytes32 name) external nonpayable
```

**Arguments**

| Name       | Type                                                     | Description                                      |
| ---------- | -------------------------------------------------------- | ------------------------------------------------ |
| document   | mapping(bytes32 => struct SecurityTokenStorage.Document) |                                                  |
| docNames   | bytes32\[]                                               |                                                  |
| docIndexes | mapping(bytes32 => uint256)                              |                                                  |
| name       | bytes32                                                  | Name of the document. It should be unique always |

### verifyTransfer

Validate transfer with TransferManager module if it exists

```javascript
function verifyTransfer(address[] modules, mapping(address => struct SecurityTokenStorage.ModuleData) modulesToData, address from, address to, uint256 value, bytes data, bool transfersFrozen) public view
returns(bool, bytes32)
```

**Returns**

bool

**Arguments**

| Name            | Type                                                       | Description                              |
| --------------- | ---------------------------------------------------------- | ---------------------------------------- |
| modules         | address\[]                                                 | Array of addresses for transfer managers |
| modulesToData   | mapping(address => struct SecurityTokenStorage.ModuleData) | Mapping of the modules details           |
| from            | address                                                    | sender of transfer                       |
| to              | address                                                    | receiver of transfer                     |
| value           | uint256                                                    | value of transfer                        |
| data            | bytes                                                      | data to indicate validation              |
| transfersFrozen | bool                                                       | whether the transfer are frozen or not.  |

### canTransfer

```javascript
function canTransfer(bool success, bytes32 appCode, address to, uint256 value, uint256 balanceOfFrom) external pure
returns(bytes1, bytes32)
```

**Arguments**

| Name          | Type    | Description |
| ------------- | ------- | ----------- |
| success       | bool    |             |
| appCode       | bytes32 |             |
| to            | address |             |
| value         | uint256 |             |
| balanceOfFrom | uint256 |             |

### \_getKey

```javascript
function _getKey(bytes32 _key1, address _key2) internal pure
returns(bytes32)
```

**Arguments**

| Name   | Type    | Description |
| ------ | ------- | ----------- |
| \_key1 | bytes32 |             |
| \_key2 | address |             |

### \_isExistingInvestor

```javascript
function _isExistingInvestor(address _investor, IDataStore dataStore) internal view
returns(bool)
```

**Arguments**

| Name       | Type       | Description |
| ---------- | ---------- | ----------- |
| \_investor | address    |             |
| dataStore  | IDataStore |             |