# DEX 合约间依赖 (DEX Inter—Contract Dependencies)

To ensure deterministic outcome, we ask contract developers to explicitly specify what other contract dependencies their contract has, during registration with the DEX module. **Contract A is considered to depend on contract B if the response of any of contract A's** **`sudo`** **calls may contain order placement/cancellation messages to contract B**. For example, a perp contract might need to place orders on a spot contract during its own order placement process to support features like multi-collateral. In that case, the perp contract will need to specify its dependency on the spot contract. The CLI syntax to register a contract with dependencies is as follow:

为了保证确定性的结果，我们要求合约开发人员在向 DEX 模块注册期间明确指定他们的合约具有哪些其他合约依赖项。 **如果合约A的任何响应** **`sudo`** **调用可能包含对合约B的下单/取消消息**，则合约A被视为依赖于合约B。例如，永续合约可能需要在其自己的下单过程中对现货合约下订单，以支持多抵押等功能。在这种情况下，永久合约将需要指定其对现货合约的依赖。使用依赖项注册合约的 CLI 语法如下：

```
seid tx dex register-contract [contract address] [code id] \
    [need hook] [need order matching] [dependency1,dependency2,...]
```

In the above perp-spot example, assuming perp's address is `sei14hj2tavq8fpesdwxxcu44rty3hh90vhujrvcmstl4zr3txmfvw9sh9m79m` and spot's address is `sei1fzm6gzyccl8jvdv3qq6hp9vs6ylaruervs4m06c7k0ntzn2f8faq8un0p6`, the CLI to register perp would be:

在上面的 perp-spot 示例中，假设永续合约的地址是 `sei14hj2tavq8fpesdwxxcu44rty3hh90vhujrvcmstl4zr3txmfvw9sh9m79m` 并且现货的地址是 `sei1fzm6gzyccl8jvdv3qq6hp9vs6ylaruervs4m06c7k0ntzn2f8fapq8un06`，CLI 将注册：

```
seid tx dex register-contract sei14hj2tavq8fpesdwxxcu44rty3hh90vhujrvcmstl4zr3txmfvw9sh9m79m \
    1 true true sei1fzm6gzyccl8jvdv3qq6hp9vs6ylaruervs4m06c7k0ntzn2f8faq8un0p6
```

Note that the registration is an upsert operation, so registering the same contract multiple times will update its registration information.

注意注册是一个合并(upsert)操作，所以多次注册同一个合约会更新它的注册信息。

#### 循环依赖 (Circular Dependency)

Circular dependency is not allowed and will be rejected if detected upon contract registration. For example, if contract A is already registered to depend on contract B, then a registration of contract B that specifies contract A as a dependency will fail.

不允许循环依赖，如果在合约注册时检测到，将被拒绝。例如，如果合约A已经注册为依赖于合约B，那么将合约A指定为依赖项的合约B的注册将失败。