> ## Documentation Index
> Fetch the complete documentation index at: https://praison.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# expr • Rust AI Agent SDK

> expr: Create an expression condition.

# expr

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  <Badge color="purple">Method</Badge>
</div>

> This is a method of the [**If**](../classes/If) class in the [**conditions**](../modules/conditions) module.

Create an expression condition.

## Signature

```python theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
def expr(expression: impl Into<String>) -> ExpressionCondition
```

## Parameters

<ParamField query="expression" type="impl Into<String>" required={true}>
  No description available.
</ParamField>

### Returns

<ResponseField name="Returns" type="ExpressionCondition">
  The result of the operation.
</ResponseField>