Variable Operators

Like the jq equivalents, variables are sometimes required for the more complex expressions (or swapping values between fields).
Note that there is also an additional ref operator that holds a reference (instead of a copy) of the path, allowing you to make multiple changes to the same path.
Single value variable
Given a sample.yml file of:
a: cat
then
yq '.a as $foo | $foo' sample.yml
will output
cat
Multi value variable
Given a sample.yml file of:
- cat
- dog
then
yq '.[] as $foo | $foo' sample.yml
will output
cat
dog
Using variables as a lookup
Example taken from jq​
Given a sample.yml file of:
"posts":
  - "title": First post
    "author": anon
  - "title": A well-written article
    "author": person1
"realnames":
  "anon": Anonymous Coward
  "person1": Person McPherson
then
yq '.realnames as $names | .posts[] | {"title":.title, "author": $names[.author]}' sample.yml
will output
title: First post
author: Anonymous Coward
title: A well-written article
author: Person McPherson
Using variables to swap values
Given a sample.yml file of:
a: a_value
b: b_value
then
yq '.a as $x  | .b as $y | .b = $x | .a = $y' sample.yml
will output
a: b_value
b: a_value
Use ref to reference a path repeatedly
Note: You may find the with operator more useful.
Given a sample.yml file of:
a:
  b: thing
  c: something
then
yq '.a.b ref $x | $x = "new" | $x style="double"' sample.yml
will output
a:
  b: "new"
  c: something

Unique

With

Last modified 4mo ago