yq/pkg/yqlib/doc/operators/recursive-descent-glob.md

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# Recursive Descent (Glob)
This operator recursively matches (or globs) all children nodes given of a particular element, including that node itself. This is most often used to apply a filter recursively against all matches.
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## match values form `..`
This will, like the `jq` equivalent, recursively match all _value_ nodes. Use it to find/manipulate particular values.
For instance to set the `style` of all _value_ nodes in a yaml doc, excluding map keys:
```bash
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yq '.. style= "flow"' file.yaml
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```
## match values and map keys form `...`
The also includes map keys in the results set. This is particularly useful in YAML as unlike JSON, map keys can have their own styling and tags and also use anchors and aliases.
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For instance to set the `style` of all nodes in a yaml doc, including the map keys:
```bash
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yq '... style= "flow"' file.yaml
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```
## Recurse map (values only)
Given a sample.yml file of:
```yaml
a: frog
```
then
```bash
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yq '..' sample.yml
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```
will output
```yaml
a: frog
frog
```
## Recursively find nodes with keys
Note that this example has wrapped the expression in `[]` to show that there are two matches returned. You do not have to wrap in `[]` in your path expression.
Given a sample.yml file of:
```yaml
a:
name: frog
b:
name: blog
age: 12
```
then
```bash
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yq '[.. | select(has("name"))]' sample.yml
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```
will output
```yaml
- name: frog
b:
name: blog
age: 12
- name: blog
age: 12
```
## Recursively find nodes with values
Given a sample.yml file of:
```yaml
a:
nameA: frog
b:
nameB: frog
age: 12
```
then
```bash
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yq '.. | select(. == "frog")' sample.yml
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```
will output
```yaml
frog
frog
```
## Recurse map (values and keys)
Note that the map key appears in the results
Given a sample.yml file of:
```yaml
a: frog
```
then
```bash
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yq '...' sample.yml
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```
will output
```yaml
a: frog
a
frog
```
## Aliases are not traversed
Given a sample.yml file of:
```yaml
a: &cat
c: frog
b: *cat
```
then
```bash
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yq '[..]' sample.yml
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```
will output
```yaml
- a: &cat
c: frog
b: *cat
- &cat
c: frog
- frog
- *cat
```
## Merge docs are not traversed
Given a sample.yml file of:
```yaml
foo: &foo
a: foo_a
thing: foo_thing
c: foo_c
bar: &bar
b: bar_b
thing: bar_thing
c: bar_c
foobarList:
b: foobarList_b
!!merge <<:
- *foo
- *bar
c: foobarList_c
foobar:
c: foobar_c
!!merge <<: *foo
thing: foobar_thing
```
then
```bash
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yq '.foobar | [..]' sample.yml
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```
will output
```yaml
- c: foobar_c
!!merge <<: *foo
thing: foobar_thing
- foobar_c
- *foo
- foobar_thing
```