From: Jim Freeze <jim@...>
Date: 2004-06-24T22:40:03+09:00
Subject: N Dimensional Hash?

Hi

I'm looking for an object that behaves like a 
n-dimensional hash. We'll start with two dimensions
to make this easy.

Lets say I have the data table

 [
   %w{mini cooper   red},
   %w{ford focus    white},
   %w{ford mustang  blue},
   %w{ab   cd       1},
   %w{abc  d        2},
   %w{a    bcd      3},
 ]

Obviously I could build hash with:

  h = { "mini" => {},
        "ford" => {},
        "ab"   => {},
        "abc"  => {},
        "a"    => {}
      }

  h["mini"] = { "cooper" => "red" }
  h["ford"] = { "focus" => "white", "mustang" => "blue" }
  h["ab"]   = { "cd" => 1 }
  h["abc"]  = { "d" => 2 }
  h["a"]    = { "bcd" => 3 }

But this is painful.
Before I go and write a class to do this, is there
something that already does this. Like, maybe tuples,
which I don't understand.

...Hmm, I would describe this as a hierarchal struct with
named arguments.

 h[:make=>"mini", :model=>"cooper"] #=> "red"
 sames as:
 h[:model=>"cooper", :make=>"mini"] #=> "red"

-- 
Jim Freeze
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Advertising wondrous things.
		-- Tom Lehrer