Perl Style: Use Hashes of Records, not Parallel Arrays

Jan 1, 1998 by Tom Christiansen

• Learn to use hashes of records, and maintain array or hashes of these records, rather than using parallel arrays. Don’t do this:

      $age{"Jason"} = 23;
      $dad{"Jason"} = "Herbert";
  

  When you should do:

      $people{"Jason"}{AGE} = 23;
      $people{"Jason"}{DAD} = "Herbert";
  

  Or even: (note use of for here)

      for $his ($people{"Jason"}) {
          $his->{AGE} = 23;
          $his->{DAD} = "Herbert";
      }
  

  But think very carefully before writing this:

      @{ $people{"Jason"} }{"AGE","DAD"} = (23, "Herbert");
  

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Copyright © 1998, Tom Christiansen All rights reserved.