pub fn read_documents(
paths: &[String],
) -> Result<(Value, Vec<(String, Format)>), String>Expand description
Read several config files, in order, into ONE effective document: each later
file is merged over the previous ones with JSON Merge Patch semantics
(RFC 7396) — objects merge recursively, scalars and lists are REPLACED by the
later file, and a null value UNSETS the key. Every file is type-checked on
its own first (so an unknown key is reported against the file that carries
it), then the merged document is returned with the (path, format) list.