# Create Pool

## Create Pool

For general pool creation, use the `create_pool_v3/create_pool_v2/create_pool`    function in the `registry` module.

{% hint style="success" %}
The original `create_pool` relied on the `CoinMetadata` of both coins, so after Sui’s metadata mechanism changed and some `CoinMetadata` got destroyed, it no longer worked for those coins. `create_pool_v2` and `create_pool_v3` both support creating pools **without** coin metadata, and `create_pool_v3` is now recommended. The difference between them is how `global_config` is passed: `create_pool_v2` one uses a mutable reference, and `create_pool_v3` uses an immutable reference.
{% endhint %}

### Function params

* **registry**: the reference to the global registry.

<table><thead><tr><th width="113.15234375">network</th><th>registry object id</th></tr></thead><tbody><tr><td>mainnet</td><td>0xb1d55e7d895823c65f98d99b81a69436cf7d1638629c9ccb921326039cda1f1b</td></tr><tr><td>testnet</td><td>0x319070e26a6809f439d3c4a45e63bf74939c5fe3165de7b65968ee8547f71bd0</td></tr></tbody></table>

* **metadata\_a**: Metadata object id for token A.(`create_pool_v2`  don't need it)
* **metadata\_b**: Metadata object id for token B.(`create_pool_v2`  don't need it)
* **bin\_step**:  Bin step configuration for the pool.
* **base\_factor**: Base factor for the pool configuration

| Base fee | Bin Step | Base factor |
| -------- | -------- | ----------- |
| 0.01%    | 1        | 10,000      |
| 0.02%    | 1        | 20,000      |
| 0.03%    | 2        | 15,000      |
| 0.04%    | 2        | 20,000      |
| 0.05%    | 5        | 10,000      |
| 0.10%    | 10       | 10,000      |
| 0.15%    | 15       | 10,000      |
| 0.20%    | 20       | 10,000      |
| 0.25%    | 25       | 10,000      |
| 0.30%    | 30       | 10,000      |
| 0.40%    | 50       | 8,000       |
| 0.60%    | 80       | 7,500       |
| 0.80%    | 100      | 8,000       |
| 1.00%    | 100      | 10,000      |
| 2.00%    | 200      | 10,000      |
| 4.00%    | 400      | 10,000      |

* **active\_id**: Initial active bin ID for the pool

> #### How to calculate bin id by price?
>
> **Formula**: `bin_id = log(price) / log(1 + bin_step/10000)`
>
> **Explanation**: The bin ID represents which price level (bin) a given price falls into within a geometric sequence. Each bin is `(1 + bin_step/10000)` times larger than the previous one, where `bin_step` is measured in basis points (1/10000). The logarithm calculates how many multiplicative steps are needed to reach the target price from the base price of 1.
>
> **Example**: If `bin_step = 20` (0.2%) and `price = 1.5`, then `bin_id = log(1.5) / log(1.002) ≈ 203`, meaning the price 1.5 is at the 203rd bin in the geometric price scale.

* **url**: URL for pool metadata.
* **config**: Reference to the global config for validations

<table><thead><tr><th width="113.15234375">network</th><th>global config object id</th></tr></thead><tbody><tr><td>mainnet</td><td>0xf31b605d117f959b9730e8c07b08b856cb05143c5e81d5751c90d2979e82f599</td></tr><tr><td>testnet</td><td>0x88bb33e9eff2fccab980a0e4b43fc4572abd08f08304d47a20d3e4e99d94d159</td></tr></tbody></table>

* **versioned**: Versioned object for version checking

<table><thead><tr><th width="113.15234375">network</th><th>versioned config object id</th></tr></thead><tbody><tr><td>mainnet</td><td>0x05370b2d656612dd5759cbe80463de301e3b94a921dfc72dd9daa2ecdeb2d0a8</td></tr><tr><td>testnet</td><td>0xa710caae87b2129acc97fbb98ea7011e3137c3291b02c0fcce866d67d5d9e8d0</td></tr></tbody></table>

* **clock**: Clock object for timestamp operations. (0x6)

### Types <a href="#types" id="types"></a>

* **`coinTypeA`**: the coin type address about coinA.
* **`coinTypeB`**: the coin type address about coinB.

```rust
/// Creates a new pool for the specified token pair.
///
/// This function creates a new pool with the given configuration, validates
/// all parameters, and registers it in the global registry.
///
/// ## Type Parameters
/// - `CoinTypeA`: Type of token A in the pool
/// - `CoinTypeB`: Type of token B in the pool
///
/// ## Parameters
/// - `registry`: Mutable reference to the global registry
/// - `metadata_a`: Metadata for token A
/// - `metadata_b`: Metadata for token B
/// - `bin_step`: Bin step configuration for the pool
/// - `base_factor`: Base factor for the pool configuration
/// - `active_id`: Initial active bin ID for the pool
/// - `url`: URL for pool metadata
/// - `config`: Reference to the global config for validations
/// - `versioned`: Versioned object for version checking
/// - `clock`: Clock object for timestamp operations
/// - `ctx`: Transaction context
///
/// ## Returns
/// - `(CreatePoolReceipt, Pool)`: Tuple of receipt and created pool
///
/// ## Errors
/// - `ECoinTypeNotAllowed`: If one or both coin types are not allowed
/// - `EInvalidActiveId`: If active ID is outside valid price range
/// - `ESameCoinType`: If both token types are the same
/// - `EPoolAlreadyExist`: If pool with the same key already exists
/// - `ENoUserOperationPermission`: If sender lacks user operation permission
///
/// ## Events Emitted
/// - `CreatePoolEvent`: Contains pool creation details
public fun create_pool<CoinTypeA, CoinTypeB>(
    registry: &mut Registry,
    metadata_a: &CoinMetadata<CoinTypeA>,
    metadata_b: &CoinMetadata<CoinTypeB>,
    bin_step: u16,
    base_factor: u16,
    active_id: u32,
    url: String,
    config: &mut GlobalConfig,
    versioned: &Versioned,
    clock: &Clock,
    ctx: &mut TxContext,
): (CreatePoolReceipt, Pool<CoinTypeA, CoinTypeB>) {
    ...
}

// // use &GlobalConfig
public fun create_pool_v2<CoinTypeA, CoinTypeB>(
    registry: &mut Registry,
    bin_step: u16,
    base_factor: u16,
    active_id: u32,
    url: String,
    config: &mut GlobalConfig,
    versioned: &Versioned,
    clock: &Clock,
    ctx: &mut TxContext,
): (CreatePoolReceipt, Pool<CoinTypeA, CoinTypeB>){
    ...
}

// use &GlobalConfig
public fun create_pool_v3<CoinTypeA, CoinTypeB>(
    registry: &mut Registry,
    bin_step: u16,
    base_factor: u16,
    active_id: u32,
    url: String,
    config: &GlobalConfig,
    versioned: &Versioned,
    clock: &Clock,
    ctx: &mut TxContext,
): (CreatePoolReceipt, Pool<CoinTypeA, CoinTypeB>) {
    abort 1
}
```