On , I learnt ...

About YAML’s node anchors and aliases

I’ve seen these a few times but only today decided to actually work out how they worked.

YAML lets you define an anchor (&name) for a node, sequence or scalar that you can refer to later with an alias (*name). This lets you avoid duplication by extending or overriding objects

twin1: &person
    first: Barry
    last: Chuckle
    <<: *person
    first: Paul

For more, see http://blogs.perl.org/users/tinita/2019/05/reusing-data-with-yaml-anchors-aliases-and-merge-keys.html