fix(doc): update documentation regarding (non)empty Root
@@ -218,6 +218,14 @@ The initial definition of a VName includes the following 5 fields:
to designate virtual collections like generated files.
+
+
+ An empty Root field should signify a concrete file in the corpus
+ relative to the corpus root. The interpretation for a VName with an
+ empty Root corresponds to a file under version control in (one of)
+ the repository(ies) being analyzed; a non-empty Root indicates a
+ generated file, for which the Root is typically (part of) a prefix
+ to the path of that file.
+ +
+ +
_Rationale:_ Usually a corpus will comprise a single rooted tree of files,
such as a Git repository -- in which case the Root field can be left empty.
In some cases, though, a corpus may have more than one tree -- for example,
