Use these comment operators to set or retrieve comments.
Like the = and |= assign operators, the same syntax applies when updating comments:
plain form: =
This will assign the LHS nodes comments to the expression on the RHS. The RHS is run against the matching nodes in the pipeline
relative form: |=
Similar to the plain form, however the RHS evaluates against each matching LHS node! This is useful if you want to set the comments as a relative expression of the node, for instance its value or path.
Set line comment
Given a sample.yml file of:
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a: cat
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then
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yq eval'.a lineComment="single"' sample.yml
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will output
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a: cat # single
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Use update assign to perform relative updates
Given a sample.yml file of:
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a: cat
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b: dog
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then
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yq eval'.. lineComment |= .' sample.yml
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will output
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a: cat # cat
2
b: dog # dog
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Set head comment
Given a sample.yml file of:
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a: cat
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then
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yq eval'. headComment="single"' sample.yml
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will output
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# single
2
3
a: cat
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Set foot comment, using an expression
Given a sample.yml file of:
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a: cat
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then
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yq eval'. footComment=.a' sample.yml
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will output
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a: cat
2
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# cat
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Remove comment
Given a sample.yml file of:
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a: cat # comment
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b: dog # leave this
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then
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yq eval'.a lineComment=""' sample.yml
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will output
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a: cat
2
b: dog # leave this
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Remove (strip) all comments
Note the use of ... to ensure key nodes are included.