Would the following setup be something nice? This just came to mind while reading this awesome feature request, so I haven’t given it a lot of thought yet… (yes, that is a disclaimer that this idea might turn out to be garbage one or to posts down the line).
Edit: thanks @SirCaptain for very clearly summarizing points 2 and 4! 
I would love it if this became reality:
- You define a tag hierarchy/taxonomy in the Library like you define your Object Types and Relations (just add another tab next to Types and Relations). You only need to setup a “Tag category” but you can immediately populate the category with (nested) tags. Example:
- [Tag Category] Disease Timeline
- [Tag] Chronic
- [Tag] Acute
- [Tag Category] Anytype
- [Tag] Sprint Review
- [Tag Category] Company Y
- [Tag] Sprint Review
- “tags as objects” and “objects as tags”. A Tag is just an Object Type that is also listed in the Library so that would allow you to define nice templates for Tags that you want to create, and it allows you to open any Tag as an Object to write a nice description what the tag mean in more detail (or other stuff you want to have in your Tag Object). When Inline-Sets are introduced, you can add an inline set in your Tag Object to list all Objects with that tag!
- A tag is added to an Object as Relation (either as its own Block similar to other Relations of Type Object, or inline using # like you can currently add inline @-mentions). When using either method to add a tag, a suggestion should be made to create a new tag from scratch of there is no exact match. Additionally, either individual tags, Objects that are marked as a tag, or tags within a taxonomy should be suggested. If we reuse the example taxonomy from above, typing “#cute” should suggst to create the tag “cute” from scratch, but also suggest to add “Acute” or “Disease Timeline/Acute” as a tag. Which tags to suggest and in what order might need some more thought, but I expect some kind of relevancy score system is needed.
- “tags as objects” and “objects as tags”. Any Object can be marked as a Tag for one or more Tag Category to add this Object as a member of that Category. You would need to pick a Category and a place in the tree of that Category to give it the right place in the tree. For example, if you select the Category your Object will be added as a child of that Category, but if you select any of the existing children in that Category it will be a child of that child (a grandchild of the Category if you will
). Hopefully this can be achieved by adding a bool option to Objects like “isTag” to allow it to show up when adding tags. - This setup should allow Tags to be reordered/moved with a Category AND Tags can existing in multiple Categories. Sometimes you might need to have a specific tag: Bug (software) vs Bug (organism). Sometimes you might need a more general tag: “Sprint Review” can be a tag in Category “Anytype” as well as “Company Y” (if that is how you want to structure your tags). Deleting the Object would result in the same visual indication where the original name/title of the tag is still visible, but it is greyed out and has a “deleted” badge.