Module Sexp_helpers.Error_context

Embed context to make parsing errors more user-friendly.

We're using a custom exception that allows embedding special context whose purpose is to improve the parsing errors that dunolint prints to the users.

For example, when we fail to find a match for a particular construct or keyword looked up by name, we give the list of known ones so as to allow messages like: "Did you mean X?".

The way we integrate this with the raising mecanism of Sexplib0 is to embed the context into the exception type defined below, and have such exception be the first argument to the Of_sexp_error (e, _) error.