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

# Keys

Use the `keys` operator to return map keys or array indices. 

## Check node is a key
Given a sample.yml file of:
```yaml
a: frog
```
then
```bash
yq '[... | { "p": path | join("."), "isKey": is_key, "tag": tag }]' sample.yml
```
will output
```yaml
- p: ""
  isKey: false
  tag: '!!map'
- p: a
  isKey: true
  tag: null
  '!!str': null
- p: a
  isKey: false
  tag: '!!str'
```
Update document generation script 2021-11-03 04:00:58 +00:00			`# Keys`

			Use the `keys` operator to return map keys or array indices.

Added is_key operator 2022-09-30 00:27:35 +00:00			`## Check node is a key`
			`Given a sample.yml file of:`
			```yaml
wip - rabbit hole :/ 2023-05-02 04:07:59 +00:00			`a: frog`
Added is_key operator 2022-09-30 00:27:35 +00:00			```
			`then`
			```bash
			`yq '[... \| { "p": path \| join("."), "isKey": is_key, "tag": tag }]' sample.yml`
			```
			`will output`
			```yaml
			`- p: ""`
			`isKey: false`
			`tag: '!!map'`
			`- p: a`
			`isKey: true`
wip - rabbit hole :/ 2023-05-02 04:07:59 +00:00			`tag: null`
			`'!!str': null`
Added is_key operator 2022-09-30 00:27:35 +00:00			`- p: a`
			`isKey: false`
			`tag: '!!str'`
			```