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Git Source Inherits: ERC20, ERC20Burnable, ReentrancyGuard, RulesEngineClientERC20, Ownable Author: @mpetersoCode55, @ShaneDuncan602, @TJ-Everett, @VoR0220 This contract demonstrates how to integrate the Rules Engine with an ERC20 token for policy enforcement. This contract is an example implementation of an ERC20 token integrated with the Rules Engine. It extends the OpenZeppelin ERC20 and ERC20Burnable contracts and includes additional functionality for interacting with the Rules Engine. The contract ensures compliance with policies defined in the Rules Engine for minting, transferring, and transferring tokens on behalf of others.

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Functions

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constructor

Constructor for the Example ERC20 token. Initializes the token with a name and symbol. 
constructor(string memory _name, string memory _symbol) ERC20(_name, _symbol) Ownable(msg.sender);
Parameters
NameTypeDescription
_namestringThe name of the token.
_symbolstringThe symbol of the token.

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setCallingContractAdmin

Override the default setCallingContractAdmin and add onlyOwner modifier to prevent unauthorized access 
function setCallingContractAdmin(address callingContractAdmin) public override onlyOwner;

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setRulesEngineAddress

Override the default setRulesEngineAddress and add onlyOwner modifier to prevent unauthorized access 
function setRulesEngineAddress(address rulesEngine) public override onlyOwner;

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mint

Mints new tokens to a specified address. This function interacts with the Rules Engine to ensure compliance with minting policies. 
function mint(address to, uint256 amount)
    public
    virtual
    onlyOwner
    checksPoliciesERC20MintBefore(to, amount, balanceOf(msg.sender), balanceOf(to), block.timestamp);
Parameters
NameTypeDescription
toaddressThe recipient address.
amountuint256The number of tokens to mint.

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transfer

Transfers tokens to a specified address. This function overrides the IERC20-transfer function and interacts with the Rules Engine to ensure compliance with transfer policies. It includes a reentrancy guard to prevent reentrancy attacks. 
function transfer(address to, uint256 amount)
    public
    virtual
    override
    nonReentrant
    checksPoliciesERC20TransferBefore(to, amount, balanceOf(msg.sender), balanceOf(to), block.timestamp)
    returns (bool);
Parameters
NameTypeDescription
toaddressThe recipient address.
amountuint256The number of tokens to transfer.
Returns
NameTypeDescription
<none>boolbool True if the transfer is successful, false otherwise.

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transferFrom

Transfers tokens on behalf of another address. This function overrides the IERC20-transferFrom function and interacts with the Rules Engine to ensure compliance with transfer policies. It includes a reentrancy guard to prevent reentrancy attacks. 
function transferFrom(address from, address to, uint256 amount)
    public
    virtual
    override
    nonReentrant
    checksPoliciesERC20TransferFromBefore(from, to, amount, balanceOf(from), balanceOf(to), block.timestamp)
    returns (bool);
Parameters
NameTypeDescription
fromaddressThe address to transfer tokens from.
toaddressThe recipient address.
amountuint256The number of tokens to transfer.
Returns
NameTypeDescription
<none>boolbool True if the transfer is successful, false otherwise.