yq/pkg/yqlib/doc/operators/length.md

# Length

Returns the lengths of the nodes. Length is defined according to the type of the node.

## String length
returns length of string

Given a sample.yml file of:
```yaml
{a: cat}
```
then
```bash
yq '.a | length' sample.yml
```
will output
```yaml
3
```

## null length
Given a sample.yml file of:
```yaml
{a: null}
```
then
```bash
yq '.a | length' sample.yml
```
will output
```yaml
0
```

## Map length
returns number of entries

Given a sample.yml file of:
```yaml
{a: cat, c: dog}
```
then
```bash
yq 'length' sample.yml
```
will output
```yaml
2
```

## Array length
returns number of elements

Given a sample.yml file of:
```yaml
[2, 4, 6, 8]
```
then
```bash
yq 'length' sample.yml
```
will output
```yaml
4
```