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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 file-name-from-path from the file.ss module in MzLib?. This function returns the file name specified by a path, if one exists, or #f. For example:

> (require (lib "file.ss"))
> (current-directory)
#<path:/home/pg/nhw/shared/annealing/analysis>
> (file-name-from-path (build-path (current-directory) "plot.ss"))  ; a file
#<path:plot.ss>
> (file-name-from-path (current-directory)) ; a directory
#<path:analysis>
> (file-name-from-path "..") ; no name exists
#f

Discussion

Note that the string returned by file-name-from-path 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.

file-name-from-path uses the built-in split-path to split a path into constituents.

Comments about this recipe

Contributors

-- NoelWelsh - 01 Feb 2006