+* A Nit module (file).
+ In this case, only this single module is considered
+* A Nit group (directory).
+ In this case, all the modules of the groups (and recursively the sub-groups) are considered
+* A normal directory.
+ In this case, all its entries are analysed.
+ Files that are Nit modules and directories that are Nit groups are considered.
+ Other files and directories are ignored.