# Object.find_key

## Function

Returns the first key name for which the callback result is true.

## Syntax

```bt
object.find_key(callback)
```

## Parameters

| Parameters | Type | Required | Default value | Description |
| ------ | ------ | ------ | ------ | ------ |
| callback | Fn | No | Empty | The callback signature is fn(value, key, current). |

## Return value

| Type | Description |
| ------ | ------ |
| String/Empty | Returns the key name if found, otherwise returns Empty. |

## Example

```bt
data = {a: 1, b: 2, c: 3}
result = data.find_key(fn(value) { value > 1 })

// Output: b
print result
```

## Notes

- find_key traverses objects in order of insertion.
- The traversal stops as soon as the first matching key is found.