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Extracting the File Name from a Path

Problem

You want to extract just the file name from a path. For example, given a path such as "foo/bar/baz.ss" you want to extract "baz.ss"

Solution

Use split-path to split a path into constituents. The following code performs this function:

;; path->file-name : path -> (U path #f)
  (define (path->file-name path)
    (let-values (((base name must-be-dir?)
                  (split-path path)))
      (if (symbol? name)
          #f
          name)))

An example of it's usage:

> (current-directory)
#<path:/home/pg/nhw/shared/annealing/analysis>
> (path->file-name (current-directory))
#<path:analysis>
> (path->file-name "..")
#f

Discussion

Note that the file name returned by path->file-name may actually be the name of a directory, if the path denotes a directory.

If the last part of the path denotes a relative directory or the current directory (e.g. ".." or ".") then #f will be returned. Use simplify-path to ensure a file name does exist.

Comments about this recipe

Contributors

-- NoelWelsh - 01 Feb 2006