#@ load("@ytt:overlay", "overlay")

#! Out of the total set of documents, select only those
#!   that contain the key: "type" with the value "book"
#@overlay/match by=overlay.subset({"type": "book"}), expects="1+"
---
modified: true

#! For more on `overlay.subset()`:
#!   https://carvel.dev/ytt/docs/latest/lang-ref-ytt-overlay/#overlaysubset
