# Flatten

This recursively flattens arrays.

## Flatten

Recursively flattens all arrays

Given a sample.yml file of:

```yaml
- 1
- - 2
- - - 3
```

then

```bash
yq 'flatten' sample.yml
```

will output

```yaml
- 1
- 2
- 3
```

## Flatten with depth of one

Given a sample.yml file of:

```yaml
- 1
- - 2
- - - 3
```

then

```bash
yq 'flatten(1)' sample.yml
```

will output

```yaml
- 1
- 2
- - 3
```

## Flatten empty array

Given a sample.yml file of:

```yaml
- []
```

then

```bash
yq 'flatten' sample.yml
```

will output

```yaml
[]
```

## Flatten array of objects

Given a sample.yml file of:

```yaml
- foo: bar
- - foo: baz
```

then

```bash
yq 'flatten' sample.yml
```

will output

```yaml
- foo: bar
- foo: baz
```