# Noah Factory

## Contract info

**Contract name:**  Noah Factory

View [NoahFactory.sol on Github.](https://github.com/NoaharkEVM/noah-contract/blob/main/projects/exchange-protocol/contracts/NoahFactory.sol)

**EOS EVM  Network**\
Contract address**:** 0x75782A57c6522B8B17FCc01Ff11759f4535b2752\
View the [Noah Swap:Factory contract on evm](https://explorer.evm.eosnetwork.com/address/0x75782A57c6522B8B17FCc01Ff11759f4535b2752)

## Read functions

### getPair

`function getPair(address tokenA, address tokenB) external view returns (address pair);`

Address for `tokenA` and address for `tokenB` return address of pair contract (where one exists).

`tokenA` and `tokenB` order is interchangeable.

Returns `0x0000000000000000000000000000000000000000` as address where no pair exists.

### allPairs

`function allPairs(uint) external view returns (address pair);`

Returns the address of the `n`th pair (`0`-indexed) created through the Factory contract.

Returns `0x0000000000000000000000000000000000000000` where pair has not yet been created.

Begins at `0` for first created pair.

### allPairsLength

`function allPairsLength() external view returns (uint);`

Displays the current number of pairs created through the Factory contract as an integer.

### feeTo

`function feeTo() external view returns (address);`

The address to where non-LP-holder fees are sent.

### getFeeRate \#

`function` getFeeRate`(`address pair`) external view returns (uint);`

The right to set the handling fee for each pair, the default is 0.3%.

## Write functions

### createPair

function createPair(address tokenA, address tokenB) external returns (address pair);

Creates a pair for `tokenA` and `tokenB` where a pair doesn't already exist.

`tokenA` and `tokenB` order is interchangeable.

Emits `PairCreated` (see Events).

### setFeeTo

function setFeeTo(address account) external returns ();

Sets address for `feeTo`.

### setFeeRate

function setFeeRate(address pair,`uint`) external returns ();

Set the handling fee for each pair.

### toggleState

function toggleState() external returns ();

Set the contract switch and update the status once.

## Events

### PairCreated

`event PairCreated(address indexed token0, address indexed token1, address pair, uint);`

Emitted whenever a `createPair` creates a new pair.

`token0` will appear before `token1` in sort order.

The final `uint` log value will be `1` for the first pair created, `2` for the second.

### SetFeeRate

`event` SetFeeRate`(address indexed pair, uint);`

The log that is synchronized after each transaction fee is set.

## Interface

`import './interfaces/INoahFactory.sol';`

<pre><code><strong>// pragma solidity >=0.5.0;
</strong>interface INoahFactory { 
    event PairCreated(address indexed token0, address indexed token1, address pair, uint256 pid); 
    
    event SetFeeRate(address indexed pair, uint256 feeRate);
    
<strong>    // Returns uint
</strong>    // Pending  - 0
    // Active  - 1
    enum State {Pending, Active}
    
    function state() external view returns (State);
    
    function feeTo() external view returns (address);
    
    function admin() external view returns (address);
    
    function getPair(address tokenA, address tokenB) external view returns (address pair);
    
    function getFeeRate(address pair) external view returns (uint256 feeRate);
    
    function allPairs(uint256) external view returns (address pair);
    
    function allPairsLength() external view returns (uint256);
    
    function createPair(address tokenA, address tokenB) external returns (address pair);
    
    function setFeeTo(address) external;
    
    function setAdmin(address) external;
    
    function setFeeRate(address pair, uint256 _feeRate) external;
    
    function toggleState() external;
    
    function INIT_CODE_PAIR_HASH() external view returns (bytes32);
}
</code></pre>