8 The File-System Module

8.2 Types specific to file system operations

The File-System module contains a number of types specifically designed for use by interfaces in the module.

Firstly, the type <file-type> represents the types of entity that may be present on a given file system. Three entities are allowed: a file, a directory, and a link to a file or directory located elsewhere in the file system. Together, these represent any entity that can be placed on a file system mounted on the local machine. The <file-type> type is defined as

one-of(#"file", #"directory", #"link")

The type <pathname> represents the set of classes that may be used to represent pathnames that indicate entities on the file system. It is defined as a type alias of <string>.

Lastly, the type <copy/rename-disposition> represents the possible values of the if-exists: keyword to the functions rename-file and copy-file described in Section 8.3. It is defined as

one-of (#"signal", #"replace")

If the value of the keyword for either function is #"signal" (the default for both functions), then you are prompted before an existing file is overwritten as a result of a copy or rename operation. If #"replace", then an existing file is overwritten without prompting.