# Common Types

This section contains the definitions of structures used by many of our ADOs. To avoid redefining them every time, they will be placed in this section and referenced. 

## Asset

Enum that specifies the type of asset being used.

```rust
#[cw_serde]
pub enum Asset {
    Cw20Token(AndrAddr),
    NativeToken(String),
}
```

* **Cw20Token:** Specifies that the asset being used is a CW20 token. Specify the address of the CW20 contract using the [AndrAddr](#andraddr) struct.
* **NativeToken:** Specifies that the asset being used is a native token. Specify the micro denomination of the token (uandr, ustars etc...).

## Coin

### Definition <a href="#definition" id="definition"></a>

A struct used to store the denom and amount of funds.

{% tabs %}
{% tab title="Rust" %}

```rust
pub struct Coin {
    pub denom: String,
    pub amount: Uint128,
}
```

{% endtab %}

{% tab title="JSON" %}

```json
{
"denom":"uandr",
"amount":"1000000"
}
```

{% endtab %}
{% endtabs %}

| Name     | Type    | Description                    |
| -------- | ------- | ------------------------------ |
| `denom`  | String  | The denomination of the funds. |
| `amount` | Uint128 | The amount of funds.           |

## Expiration

### Definition

Expiration represents a point in time when some event happens. It can compare with a BlockInfo and will return **is\_expired() == true** once the condition is hit (and for every block in the future).

{% tabs %}
{% tab title="Rust" %}

```rust
pub enum Expiration {
    AtHeight(u64),
    AtTime(Timestamp),
    Never {},
}
```

{% endtab %}
{% endtabs %}

**AtHeight:** AtHeight will expire when `env.block.height` >= height.

**AtTime:** AtTime will expire when `env.block.time` >= time.

**Never:** Never will never expire. Used to express the empty variant.

#### Timestamp

A point in time in **nanosecond** precision.

```rust
pub struct Timestamp(Uint64)
```

#### JSON Implementation

```json
{
"expiration":{
  "at_height": 500
  }

or

{
"expiration":{
  "at_time":"1246593483949835832"
}
```

## Expiry and Milliseconds

### Expiry

The Expiry enum is used to define an expiry time using milliseconds. There are two types for Expiry:

```rust
pub enum Expiry {
    FromNow(Milliseconds),
    AtTime(Milliseconds),
}
```

* **FromNow:** The expiry time is relative to the current time. For example specifying 60000 means the expiry time is one minute from now.
* **AtTime:** The expiry time is an absolute time ([Epoch](https://www.epochconverter.com) time in milliseconds).

### Milliseconds

Struct that represents time in milliseconds in u64. We have two types that use Milliseconds:

{% hint style="info" %}
The two type were created to make the usage of the Milliseconds clearer in the different usage cases.&#x20;
{% endhint %}

* **MillisecondsDuration:** Used for instances that specify a duration in milliseconds.
* **MillisecondsExpiration:** Used for instances that spceify a timestamp in milliseconds.

```rust
#[cw_serde]
#[derive(Default, Eq, PartialOrd, Copy)]
pub struct Milliseconds(pub u64);
pub type MillisecondsDuration = Milliseconds;
pub type MillisecondsExpiration = Milliseconds;
```

## Recipient

A simple struct used for inter-contract communication:

```rust
pub struct Recipient {
    pub address: AndrAddr,
    pub msg: Option<Binary>,
    pub ibc_recovery_address: Option<AndrAddr>,
}
```

The struct can be used in two ways:

1\. Simply just providing an `AndrAddr` which will treat the communication as a transfer of any related funds.

&#x20;2\. Providing an `AndrAddr` and a `Binary` message which will be sent to the contract at the resolved address. The `Binary` message can be any message that the contract at the resolved address can handle.

{% hint style="warning" %}
The `ibc_recovery_address` is an address to receive funds in case the IBC message failed. IBC messages are currently disabled and will be enabled soon.&#x20;
{% endhint %}

### AndrAddr

An address or path that can be used within the Andromeda ecosystem to reference ADOs and users.

```rust
pub struct AndrAddr(String);
```

**The address can be one of the following:**

* A valid human readable address e.g. "**andr14pmn28jyqgphd5wv0z28ppxe5ryeraqqgqfr2v**"&#x20;
* A valid Andromeda [Virtual File System](https://docs.andromedaprotocol.io/andromeda/platform-and-framework/andromeda-messaging-protocol/virtual-file-system) (VFS) path e.g. "**/home/user/app1/component3**"
* A valid [VFS](https://docs.andromedaprotocol.io/andromeda/platform-and-framework/andromeda-messaging-protocol/virtual-file-system) local path used in Apps e.g. "**./\<component-name>**"