1. Schwartzian Transform

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   • Sort list of items by some non-apparent feature

   • Example: Sort filenames by last-modified date

   • Obvious method is very wasteful:

        sort { -M $b <=> -M $a } (readdir D);

• Calls -M over and over on the same files

• Idea:

  1. Construct data structure with both names and dates

  2. Sort by date

  3. Throw away dates

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Copyright © 2002 M-J. Dominus