From: Justin Collins <justincollins@...>
Date: 2008-02-22T07:58:59+09:00
Subject: Re: More efficient comparing

Kyle Hunter wrote:
> Hello,
>
> I've got an array that holds urls. Example Element:
> http://bla.random.com/bla.jpg.
>
> I also have images in a directory. I'd like my script to compare the
> bla.jpg from the URL with all files in a directory to make sure it's not
> a duplicate of something that's already there - if it is - delete it
> from the array. My current way of doing it uses quite a bit of
> resources, was wondering if someone could show me a more efficient
> example if possible.
>
> Current Code:
> Dir["#{$baseDir}/#{board}/#{$dateString}/**"].each do |file|
>       $imgArray.delete_if{
>         |i| i =~ /#{file.split('/').pop}/
>       }
>   

Try:

require 'set'

files = Dir["#{$baseDir}/#{board}/#{$dateString}/**"].map { |file| 
File.basename(file) }.to_set

$imgArray.delete_if {|i|  files.include? i.split("/")[-1] }


-Justin