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Posted By

vanne on 01/20/07


Tagged

rails ruby


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Using Enumerable#select to create a specific array

Published in: Ruby 

URL: http://errtheblog.com/post/608

Useful for when you need to do a find and map specific results to an array for use later

Plain TextExpand 
  1. #Instead of using:
  2. books  = Book.find(:all, :order => 'id desc', :limit => 20)
  3. comics = []
  4. books.each do |book|
  5.   comics << book if book.item_type == 'Comic'
  6. end
  7.  
  8. #OR
  9. comics  = Book.find(:all, :order => 'id desc', :limit => 20).map {|book| [book] unless book.item_type == 'Comic'}.flatten!
  10.  
  11. #Use this:
  12. books  = Book.find(:all, :order => 'id desc', :limit => 20)
  13. comics = books.select { |i| i.item_type == 'Comic' }

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