[DIAGRAM PROPOSAL] Tree Diagrams (Slim)

[Connor-Bernard]

Proposal

Initially detailed here.

Simple tree diagrams (specifically those for syllable and syntax trees). Namely, it would have the following features:

• Create nodes with no border

• Make nodes connect at the top and bottom

• Custom connections like the split nucleus or the triangle connection (the below example)

  

Currently, this is what I have found to be the analogous operations for Mermaid:

This is somewhat similar to #3989

Use Cases

This would be good for a whole host of different things. Namely, as per my and the OP of the linked stack overflow comment, it would be helpful for diagramming syntax parsing (parse trees) for NLP. Regardless, it would be helpful for any type of light-weight tree.

Screenshots

Current best-effort diagram (with existing Mermaid synatx):

Syntax

Two options:

1. Use the current flowchart diagram (this would likely be easiest as it should only require re-skinning it and adding a couple of new components).
2. Add a more useful shorthand such as the following:

tree
    DP -- D, NP
    D -- the
    NP -- Adj, NP
    adj <| big
    NP -- Adj, N
    Adj <| red
    N -- hat

Important

Since tree structures are inherently non-recursive, we can use the last mentioned reference of a symbol when parsing a root. There will only be one root (no previous reference) and it is the first symbol of the syntax; all other symbols must be previously defined.

The above example syntax would render:

Implementation

This is a proposal which I'd love to see built into mermaid by the wonderful community.