mirror of
https://github.com/mikefarah/yq.git
synced 2026-07-03 19:05:38 +00:00
3c0fd6a3e9
Add informational hints to operator documentation covering behaviors
that may differ from user expectations, particularly for those
familiar with jq:
- slice-array: clarify that slicing only works on arrays, not strings
- select: document behavior when piping select to a literal value
- equals: note bash history expansion with != operator
- create-collect-into-object: mention that shorthand {key} syntax
is not supported
- collect-into-array: explain difference between [.x | .[]] and [.x[]]
154 lines
2.1 KiB
Markdown
154 lines
2.1 KiB
Markdown
# Equals / Not Equals
|
|
|
|
This is a boolean operator that will return `true` if the LHS is equal to the RHS and `false` otherwise.
|
|
|
|
```
|
|
.a == .b
|
|
```
|
|
|
|
It is most often used with the select operator to find particular nodes:
|
|
|
|
```
|
|
select(.a == .b)
|
|
```
|
|
|
|
The not equals `!=` operator returns `false` if the LHS is equal to the RHS.
|
|
|
|
{% hint style="info" %}
|
|
|
|
_Note_ that the `!=` operator contains `!` which can trigger bash history expansion in interactive shells:
|
|
|
|
```bash
|
|
# May fail with: bash: !": event not found
|
|
yq '.status != "healthy"' file.yaml
|
|
```
|
|
|
|
Workarounds:
|
|
```bash
|
|
# Use $'...' quoting
|
|
yq $'.status != "healthy"' file.yaml
|
|
|
|
# Or use | not instead of !=
|
|
yq '.status == "healthy" | not' file.yaml
|
|
```
|
|
|
|
{% endhint %}
|
|
|
|
## Related Operators
|
|
|
|
- comparison (`>=`, `<` etc) operators [here](https://mikefarah.gitbook.io/yq/operators/compare)
|
|
- boolean operators (`and`, `or`, `any` etc) [here](https://mikefarah.gitbook.io/yq/operators/boolean-operators)
|
|
- select operator [here](https://mikefarah.gitbook.io/yq/operators/select)
|
|
|
|
|
|
## Match string
|
|
Given a sample.yml file of:
|
|
```yaml
|
|
- cat
|
|
- goat
|
|
- dog
|
|
```
|
|
then
|
|
```bash
|
|
yq '.[] | (. == "*at")' sample.yml
|
|
```
|
|
will output
|
|
```yaml
|
|
true
|
|
true
|
|
false
|
|
```
|
|
|
|
## Don't match string
|
|
Given a sample.yml file of:
|
|
```yaml
|
|
- cat
|
|
- goat
|
|
- dog
|
|
```
|
|
then
|
|
```bash
|
|
yq '.[] | (. != "*at")' sample.yml
|
|
```
|
|
will output
|
|
```yaml
|
|
false
|
|
false
|
|
true
|
|
```
|
|
|
|
## Match number
|
|
Given a sample.yml file of:
|
|
```yaml
|
|
- 3
|
|
- 4
|
|
- 5
|
|
```
|
|
then
|
|
```bash
|
|
yq '.[] | (. == 4)' sample.yml
|
|
```
|
|
will output
|
|
```yaml
|
|
false
|
|
true
|
|
false
|
|
```
|
|
|
|
## Don't match number
|
|
Given a sample.yml file of:
|
|
```yaml
|
|
- 3
|
|
- 4
|
|
- 5
|
|
```
|
|
then
|
|
```bash
|
|
yq '.[] | (. != 4)' sample.yml
|
|
```
|
|
will output
|
|
```yaml
|
|
true
|
|
false
|
|
true
|
|
```
|
|
|
|
## Match nulls
|
|
Running
|
|
```bash
|
|
yq --null-input 'null == ~'
|
|
```
|
|
will output
|
|
```yaml
|
|
true
|
|
```
|
|
|
|
## Non existent key doesn't equal a value
|
|
Given a sample.yml file of:
|
|
```yaml
|
|
a: frog
|
|
```
|
|
then
|
|
```bash
|
|
yq 'select(.b != "thing")' sample.yml
|
|
```
|
|
will output
|
|
```yaml
|
|
a: frog
|
|
```
|
|
|
|
## Two non existent keys are equal
|
|
Given a sample.yml file of:
|
|
```yaml
|
|
a: frog
|
|
```
|
|
then
|
|
```bash
|
|
yq 'select(.b == .c)' sample.yml
|
|
```
|
|
will output
|
|
```yaml
|
|
a: frog
|
|
```
|
|
|