From: "ara.t.howard" <ara.t.howard@...>
Date: 2007-10-26T00:38:59+09:00
Subject: Re: Array of Pairs data structure?


On Oct 25, 2007, at 12:40 AM, Greg Willits wrote:

> In a language called Lasso I am used to a data structure of an  
> array of
> pairs:
>
> $simpleArray = array( 'color', 'shape', 'size')
>
> $arrayofPairs = array( 'color' = 'red', 'shape' = 'trapezoid',  
> 'size' =
> 'small')
>
> $simpleMap = map( 'color' = 'red', 'shape' = 'trapezoid', 'size' =
> 'small')
>
> The difference between arrayofPairs and simpleMap is that the map  
> (hash)
> cannot gaurantee a specific order whereas the arrayofPairs does.  
> It's an
> array, so order is preserved. It also has what effectively works just
> like hash keys. I can find, retrieve, and even sort based on the first
> element of the pair. Lasso has a primitive data type of a Pair.
>
> Does Ruby have a way to create this arrayofPairs? I don't see a data
> type like a "pair" in Ruby, so not sure what to insert into each array
> element to net this same data structure except I guess maybe an  
> array of
> single key hashes?
>
> ideas? Thanks.

use arrayfields.


cfp:~ > cat a.rb
require 'rubygems'
require 'arrayfields'  ### gem install arrayfields

a = Arrayfields.new 'k', 'v', 'K', 'V'
p a['k']
p a['K']
p a

__END__

docs @ http://codeforpeople.com/lib/ruby/arrayfields/ 
arrayfields-4.5.0/README



cfp:~ > ruby a.rb
"v"
"V"
["v", "V"]



kind regards.

a @ http://codeforpeople.com/
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