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

<AgentInstructions>

## Submitting Feedback

If you encounter incorrect, outdated, or confusing documentation on this page, submit feedback:

POST https://axiom.co/docs/feedback

```json
{
  "path": "/apl/scalar-operators/in-operators/overview",
  "feedback": "Description of the issue"
}
```

Only submit feedback when you have something specific and actionable to report.

</AgentInstructions>

# Set membership operators

> Learn how to use and combine different set membership operators in APL

The table summarizes the set membership operators available in APL. These operators filter records based on whether a value matches any element in a specified set.

| Name                                                              | Description                                                    | Case-sensitive |
| ----------------------------------------------------------------- | -------------------------------------------------------------- | -------------- |
| [in](/apl/scalar-operators/in-operators/in-operator)              | Returns `true` if the value equals any of the elements.        | Yes            |
| [!in](/apl/scalar-operators/in-operators/not-in-operator)         | Returns `true` if the value doesn't equal any of the elements. | Yes            |
| [in\~](/apl/scalar-operators/in-operators/in-tilde-operator)      | Returns `true` if the value equals any of the elements.        | No             |
| [!in\~](/apl/scalar-operators/in-operators/not-in-tilde-operator) | Returns `true` if the value doesn't equal any of the elements. | No             |