Purple is a small suite of quickly hacked tools inspired by Doug Engelbart's attempt to bootstrap the addressing features of his Augment system onto HTML pages. Its purpose is simple: produce HTML documents that can be addressed at the paragraph level. It does this by automatically creating name anchors with static and hierarchical addresses at the beginning of each text node, and by displaying these addresses as links at the end of each text node.    1A  (02)

Yes, using custom tags. Example in Python, making the !join tag join strings in an array:

Not merge the values of the keys.

GitLab will perform a reverse deep merge based on the keys

It’s an alternative to using YAML anchors and is a little more flexible and readable

The W3C Annotation Working Group has a joint deliverable with the W3C Web Application Working Group called “Robust Anchoring”. This deliverable will provide a general framework for anchoring; and, although defined within the framework of annotations, the specification can also be used for other fragment identification use cases. Similarly, the W3C Media Fragments specification [media-frags] may prove useful to address some of the use cases. Finally, the Streamable Package Format draft, mentioned above, also includes a fragment identification mechanism. Would that package format be adopted for EPUB+WEB, that fragment identification may also come to the fore as an important mechanism to consider.