module Based

The Based module supports the concept of a “based” directory. Typically in modern software development, a project is represented by a set of sub-directories and files within a base directory. The exact location of the base directory is not so important (i.e. it's wherever you checked it out of source control). For a given file or sub-directory, one is often more interested in the path relative to the base directory, rather than the absolute path. (But you still need the full path when performing an actual file operation on the file or directory.) Also, there might be files and directories that you wish to ignore. Based supports simple functional includes and excludes. (A bit less succint than include/exclude globs, but probably more flexible.)