From: rpmohn@... (Ross Mohn)
Date: 2000-12-03T12:40:01+09:00
Subject: [ruby-talk:6758] Re: Array Intersect (&) question

rpmohn@panix.com (Ross Mohn) wrote in 
<8FFEE72C5rpmohnpanixcom@166.84.0.240>:

>matju@cam.org (Mathieu Bouchard) wrote in 
><Pine.LNX.3.96.1001202135505.11964A-100000@relayer>:
>
>>I think you can preserve order and use hashes.
>>
>>class Array
>>     def &(other)
>>          t = {}
>>          r = []
>>          other.each {|x| t[x]=1 }
>>          uniq.each  {|x| r<<x if t.has_key? x }
>>          r
>>     end
>>     def |(other)
>>          t = {}
>>          r = []
>>          (self+other).each {|x| r<<x unless t.has_key?(x); t[x]=1 }
>>          r
>>     end
>>     def uniq; self|[] end
>>end
>
>a1 = %w# a b c c c #
>a2 = %w# b c #
>a1 & a2 -> ["b", "c", "c", "c"]
>a2 & a1 -> ["b", "c"]
>
>I don't think that's okay:) -RPM

Oops, nevermind. I didn't see the "uniq" first time through! -RPM
-- 
Ross Mohn
rpmohn@panix.com