Context-sensitive state information

Lezer
1

Will it be possible, using Lezer, to record the “local state at the cursor” and update it dynamically? What I mean is, suppose you have an XML document, say with a lot of tags. Now suppose we are in the editor (say CodeMirror) and the XML document and cursor position look as follows:

<remark>
...
</remark>

<remark>
...   * Cursor is here
</remark>

It would be nice to know that, at the current cursor position, we are inside the second remark environment. Is that possible with Lezer and/or CodeMirror?

I have in mind eventually implementing the procedure

XML stylesheet + XML document --> HTML document

directly in CodeMirror + Lezer in this way. (Or is there a better way?)

2

If you have the syntax tree, you can use resolve to get information about the node at a given position, and then use its parent/childBefore/childAfter properties to get contextual information. The interface doesn’t expose child indices directly, since this type of tree also includes comments and such as nodes, making child indices rather useless.

3

Ok. Seems a bit inefficient to have to traverse the tree again to get this information. But I guess that is the modularity paradigm.