# FieldsV1

> FieldsV1 stores a set of fields in a data structure like a Trie, in JSON format.
> 
> Each key is either a '.' representing the field itself, and will always map to an empty set, or a string representing a sub-field or item. The string will follow one of these four formats: 'f:<name>', where <name> is the name of a field in a struct, or key in a map 'v:<value>', where <value> is the exact json formatted value of a list item 'i:<index>', where <index> is position of a item in a list 'k:<keys>', where <keys> is a map of  a list item's key fields to their unique values If a key maps to an empty Fields value, the field that key represents is part of the set.
> 
> The exact format is defined in sigs.k8s.io/structured-merge-diff

---

LLMS index: [llms.txt](/llms.txt)

---

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`apiVersion: meta/v1`

`import "k8s.io/apimachinery/pkg/apis/meta/v1"`


## FieldsV1 {#FieldsV1}

FieldsV1 stores a set of fields in a data structure like a Trie, in JSON format.

Each key is either a &#39;.&#39; representing the field itself, and will always map to an empty set, or a string representing a sub-field or item. The string will follow one of these four formats: &#39;f:&lt;name&gt;&#39;, where &lt;name&gt; is the name of a field in a struct, or key in a map &#39;v:&lt;value&gt;&#39;, where &lt;value&gt; is the exact json formatted value of a list item &#39;i:&lt;index&gt;&#39;, where &lt;index&gt; is position of a item in a list &#39;k:&lt;keys&gt;&#39;, where &lt;keys&gt; is a map of  a list item&#39;s key fields to their unique values If a key maps to an empty Fields value, the field that key represents is part of the set.

The exact format is defined in sigs.k8s.io/structured-merge-diff

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