# yq

## v4.x

- [yq](https://mikefarah.gitbook.io/yq/readme.md)
- [How It Works](https://mikefarah.gitbook.io/yq/how-it-works.md)
- [Recipes](https://mikefarah.gitbook.io/yq/recipes.md)
- [Upgrading from V3](https://mikefarah.gitbook.io/yq/upgrading-from-v3.md)
- [Evaluate](https://mikefarah.gitbook.io/yq/commands/evaluate.md): Evaluates the given expression against each yaml document in each file, in sequence
- [Evaluate All](https://mikefarah.gitbook.io/yq/commands/evaluate-all.md): Read all documents of all given yaml files into memory, then run the given expression once against the lot.
- [Shell Completion](https://mikefarah.gitbook.io/yq/commands/shell-completion.md): Generate a shell completion file for supported shells (bash/fish/zsh/powershell)
- [Operators](https://mikefarah.gitbook.io/yq/operators.md)
- [Add](https://mikefarah.gitbook.io/yq/operators/add.md)
- [Alternative (Default value)](https://mikefarah.gitbook.io/yq/operators/alternative-default-value.md)
- [Anchor and Alias Operators](https://mikefarah.gitbook.io/yq/operators/anchor-and-alias-operators.md)
- [Array to Map](https://mikefarah.gitbook.io/yq/operators/array-to-map.md)
- [Assign (Update)](https://mikefarah.gitbook.io/yq/operators/assign-update.md)
- [Boolean Operators](https://mikefarah.gitbook.io/yq/operators/boolean-operators.md)
- [Collect into Array](https://mikefarah.gitbook.io/yq/operators/collect-into-array.md)
- [Column](https://mikefarah.gitbook.io/yq/operators/column.md)
- [Comment Operators](https://mikefarah.gitbook.io/yq/operators/comment-operators.md)
- [Compare Operators](https://mikefarah.gitbook.io/yq/operators/compare.md)
- [Contains](https://mikefarah.gitbook.io/yq/operators/contains.md)
- [Create, Collect into Object](https://mikefarah.gitbook.io/yq/operators/create-collect-into-object.md)
- [Date Time](https://mikefarah.gitbook.io/yq/operators/datetime.md)
- [Delete](https://mikefarah.gitbook.io/yq/operators/delete.md)
- [Divide](https://mikefarah.gitbook.io/yq/operators/divide.md)
- [Document Index](https://mikefarah.gitbook.io/yq/operators/document-index.md)
- [Encode / Decode](https://mikefarah.gitbook.io/yq/operators/encode-decode.md)
- [Entries](https://mikefarah.gitbook.io/yq/operators/entries.md)
- [Env Variable Operators](https://mikefarah.gitbook.io/yq/operators/env-variable-operators.md)
- [Equals](https://mikefarah.gitbook.io/yq/operators/equals.md)
- [Eval](https://mikefarah.gitbook.io/yq/operators/eval.md)
- [File Operators](https://mikefarah.gitbook.io/yq/operators/file-operators.md)
- [Filter Operator](https://mikefarah.gitbook.io/yq/operators/filter.md)
- [First Operator](https://mikefarah.gitbook.io/yq/operators/first.md)
- [Flatten](https://mikefarah.gitbook.io/yq/operators/flatten.md)
- [Group By](https://mikefarah.gitbook.io/yq/operators/group-by.md)
- [Has](https://mikefarah.gitbook.io/yq/operators/has.md)
- [Keys](https://mikefarah.gitbook.io/yq/operators/keys.md)
- [Kind](https://mikefarah.gitbook.io/yq/operators/kind.md)
- [Length](https://mikefarah.gitbook.io/yq/operators/length.md)
- [Line](https://mikefarah.gitbook.io/yq/operators/line.md)
- [Load](https://mikefarah.gitbook.io/yq/operators/load.md)
- [Min](https://mikefarah.gitbook.io/yq/operators/min.md)
- [Map](https://mikefarah.gitbook.io/yq/operators/map.md)
- [Max](https://mikefarah.gitbook.io/yq/operators/max.md)
- [Modulo](https://mikefarah.gitbook.io/yq/operators/modulo.md)
- [Multiply (Merge)](https://mikefarah.gitbook.io/yq/operators/multiply-merge.md)
- [Omit](https://mikefarah.gitbook.io/yq/operators/omit.md)
- [Parent](https://mikefarah.gitbook.io/yq/operators/parent.md)
- [Path](https://mikefarah.gitbook.io/yq/operators/path.md)
- [Pick](https://mikefarah.gitbook.io/yq/operators/pick.md)
- [Pipe](https://mikefarah.gitbook.io/yq/operators/pipe.md)
- [Pivot](https://mikefarah.gitbook.io/yq/operators/pivot.md)
- [Recursive Descent (Glob)](https://mikefarah.gitbook.io/yq/operators/recursive-descent-glob.md)
- [Reduce](https://mikefarah.gitbook.io/yq/operators/reduce.md)
- [Reverse](https://mikefarah.gitbook.io/yq/operators/reverse.md)
- [Select](https://mikefarah.gitbook.io/yq/operators/select.md)
- [Shuffle](https://mikefarah.gitbook.io/yq/operators/shuffle.md)
- [Slice Array](https://mikefarah.gitbook.io/yq/operators/slice-array.md)
- [Sort](https://mikefarah.gitbook.io/yq/operators/sort.md)
- [Sort Keys](https://mikefarah.gitbook.io/yq/operators/sort-keys.md)
- [Split into Documents](https://mikefarah.gitbook.io/yq/operators/split-into-documents.md)
- [String Operators](https://mikefarah.gitbook.io/yq/operators/string-operators.md)
- [Style](https://mikefarah.gitbook.io/yq/operators/style.md)
- [Subtract](https://mikefarah.gitbook.io/yq/operators/subtract.md)
- [System](https://mikefarah.gitbook.io/yq/operators/system-operators.md)
- [Tag](https://mikefarah.gitbook.io/yq/operators/tag.md)
- [To Number](https://mikefarah.gitbook.io/yq/operators/to_number.md)
- [Traverse (Read)](https://mikefarah.gitbook.io/yq/operators/traverse-read.md)
- [Union](https://mikefarah.gitbook.io/yq/operators/union.md)
- [Unique](https://mikefarah.gitbook.io/yq/operators/unique.md)
- [Variable Operators](https://mikefarah.gitbook.io/yq/operators/variable-operators.md)
- [With](https://mikefarah.gitbook.io/yq/operators/with.md)
- [Output format](https://mikefarah.gitbook.io/yq/usage/output-format.md): Flags to control yaml and json output format
- [Working with Base64](https://mikefarah.gitbook.io/yq/usage/base64.md)
- [Working with CSV, TSV](https://mikefarah.gitbook.io/yq/usage/csv-tsv.md)
- [Working with JSON](https://mikefarah.gitbook.io/yq/usage/convert.md)
- [Working with Properties](https://mikefarah.gitbook.io/yq/usage/properties.md)
- [Working with XML](https://mikefarah.gitbook.io/yq/usage/xml.md)
- [Working with HCL](https://mikefarah.gitbook.io/yq/usage/hcl.md)
- [Working with LUA](https://mikefarah.gitbook.io/yq/usage/lua.md)
- [Working with TOML](https://mikefarah.gitbook.io/yq/usage/toml.md)
- [Working with KYAML](https://mikefarah.gitbook.io/yq/usage/kyaml.md)
- [Working with Shell Output](https://mikefarah.gitbook.io/yq/usage/shellvariables.md)
- [Front Matter](https://mikefarah.gitbook.io/yq/usage/front-matter.md)
- [Split into multiple files](https://mikefarah.gitbook.io/yq/usage/split-into-multiple-files.md)
- [GitHub Action](https://mikefarah.gitbook.io/yq/usage/github-action.md)
- [Tips, Tricks, Troubleshooting](https://mikefarah.gitbook.io/yq/usage/tips-and-tricks.md)

## v3.x

- [yq](https://mikefarah.gitbook.io/yq/v3.x/master.md): yq is a lightweight and portable command-line YAML processor
- [Upgrading from V2](https://mikefarah.gitbook.io/yq/v3.x/upgrading-from-v2.md): New features and breaking changes
- [Read](https://mikefarah.gitbook.io/yq/v3.x/commands/read.md): Returns matching nodes/values of a path expression for a given yaml document
- [Validate](https://mikefarah.gitbook.io/yq/v3.x/commands/validate.md): Validate a given yaml file
- [Compare](https://mikefarah.gitbook.io/yq/v3.x/commands/compare.md): Deeply compare two yaml documents
- [Write](https://mikefarah.gitbook.io/yq/v3.x/commands/write-update.md): Updates all the matching nodes of path expression in a yaml file to the supplied value.
- [Create](https://mikefarah.gitbook.io/yq/v3.x/commands/create.md)
- [Delete](https://mikefarah.gitbook.io/yq/v3.x/commands/delete.md): Deletes all the matching nodes for the path expression in the given yaml input
- [Merge](https://mikefarah.gitbook.io/yq/v3.x/commands/merge.md): Merge multiple yaml files into a one
- [Prefix](https://mikefarah.gitbook.io/yq/v3.x/commands/prefix.md): Prefixes a yaml document with the given path expression. The complete yaml content will be nested inside the new prefix path.
- [Shell Completion](https://mikefarah.gitbook.io/yq/v3.x/commands/shell-completion.md): Generate a shell completion file for supported shells (bash/fish/zsh/powershell)
- [Output format](https://mikefarah.gitbook.io/yq/v3.x/usage/output-format.md): Flags to control yaml and json output format
- [Path Expressions](https://mikefarah.gitbook.io/yq/v3.x/usage/path-expressions.md): Path expressions are used to deeply navigate and match particular yaml nodes.
- [Value Parsing](https://mikefarah.gitbook.io/yq/v3.x/usage/value-parsing.md): How values are parsed from the CLI to commands that create/update yaml (e.g. new/write).
- [Working with JSON](https://mikefarah.gitbook.io/yq/v3.x/usage/convert.md)


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