From: Trans <transfire@...>
Date: 2007-12-01T02:59:26+09:00
Subject: Re: FileUtils, a useful extension



On Nov 30, 12:07 pm, Christophe Mckeon <chromatoph...@gmail.com>
wrote:
> i find these come in real handy, and thought they would be good for
> inclusion into FileUtils or barring that, then maybe the guys at Facets
> lib might be interested. they are based on Unix shell test options, i.e.
> [ -d somedir ] etc.
> it would be fairly trivial to implement the other test options as well.
>
> module FileUtils
>
>   def b? path
>     File.blockdev? path
>   end
>
>   def c? path
>     File.chardev? path
>   end
>
>   def d? path
>     File.directory? path
>   end
>
>   def e? path
>     File.exists? path
>   end
>
>   def f? path
>     File.file? path
>   end
>
>   def x?
>     File.executable? path
>   end

Hmmm... you know about Kernel#test ? Eg.

  test ?d, path

instead of

  FileUtils.directory?(path)


$ ri Kernel#test

------------------------------------------------------------
Kernel#test
     test(int_cmd, file1 [, file2] ) => obj
------------------------------------------------------------------------
      Uses the integer <em>aCmd</em> to perform various tests on
      <em>file1</em> (first table below) or on <em>file1</em> and
      <em>file2</em> (second table).

      File tests on a single file:

        Test   Returns   Meaning
         ?A  | Time    | Last access time for file1
         ?b  | boolean | True if file1 is a block device
         ?c  | boolean | True if file1 is a character device
         ?C  | Time    | Last change time for file1
         ?d  | boolean | True if file1 exists and is a directory
         ?e  | boolean | True if file1 exists
         ?f  | boolean | True if file1 exists and is a regular file
         ?g  | boolean | True if file1 has the \CF{setgid} bit
             |         | set (false under NT)
         ?G  | boolean | True if file1 exists and has a group
             |         | ownership equal to the caller's group
         ?k  | boolean | True if file1 exists and has the sticky bit
set
         ?l  | boolean | True if file1 exists and is a symbolic link
         ?M  | Time    | Last modification time for file1
         ?o  | boolean | True if file1 exists and is owned by
             |         | the caller's effective uid
         ?O  | boolean | True if file1 exists and is owned by
             |         | the caller's real uid
         ?p  | boolean | True if file1 exists and is a fifo
         ?r  | boolean | True if file1 is readable by the effective
             |         | uid/gid of the caller
         ?R  | boolean | True if file is readable by the real
             |         | uid/gid of the caller
         ?s  | int/nil | If file1 has nonzero size, return the size,
             |         | otherwise return nil
         ?S  | boolean | True if file1 exists and is a socket
         ?u  | boolean | True if file1 has the setuid bit set
         ?w  | boolean | True if file1 exists and is writable by
             |         | the effective uid/gid
         ?W  | boolean | True if file1 exists and is writable by
             |         | the real uid/gid
         ?x  | boolean | True if file1 exists and is executable by
             |         | the effective uid/gid
         ?X  | boolean | True if file1 exists and is executable by
             |         | the real uid/gid
         ?z  | boolean | True if file1 exists and has a zero length

     Tests that take two files:

         ?-  | boolean | True if file1 and file2 are identical
         ?=  | boolean | True if the modification times of file1
             |         | and file2 are equal
         ?<  | boolean | True if the modification time of file1
             |         | is prior to that of file2
         ?>  | boolean | True if the modification time of file1
             |         | is after that of file2

T.