Slyde is build on the mentality of "let it crash". I will try to make Slyde crash when it reaches an invalid state, and mention where this mistake in the document was. I try to provide you with a path to the invalid node.

For example this obviously does not make sense:

<presentation title="outer presentation">
  <presentation title="inner presentation" />
</presentation>

So, you'll receive an error along the lines of:

Error: Expected slides at ${path} but found presentation.

where path is the path to the inner presentation. These paths are based on xpath, a XML query language. This makes sure we are all on the same page, and might make creating IDE extensions easier later.

In case you do not get a path, that is a shame. Feel free to open an issue and I will look into it.