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cmd/config/docs/commands/merge3.md

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+## merge3
+
+[Alpha] Merge Resource configuration files (3-way)
+
+### Synopsis
+
+[Alpha] Merge Resource configuration files (3-way)
+
+Merge (3-way) reads Kubernetes Resource yaml configuration files from source packages and updated
+packages then writes the result to stdout and a destination package.
+
+Resources are merged using the Resource [apiVersion, kind, name, namespace] as the key.  If any of
+these are missing, merge will default the missing values to empty.
+
+Resources specified in the updated packages have higher-precedence and Resources specified
+in the original packages have lower-precedence.  Resources specified in the destination
+packages either keep, clear, or recursively merge their values.
+
+For information on merge rules, run:
+
+	kustomize config docs merge3
+
+### Examples
+
+    kustomize config merge3 --ancestor a/ --from b/ --to c/