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Posted By

jarnaldich on 04/05/08


Tagged

array hash


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Turning array values into hash keys

Published in: Ruby 

Useful for speeding up searches.


Plain TextExpand 
  1. # a is the array we want to turn into a hash
  2. Hash[*a.zip([true] * a.size).flatten]
  3.  
  4. # Example:
  5. people= %w[John Mary Paul]
  6. query_people=Hash[*people.zip([true] * people.size).flatten]
  7.  
  8. query_people["John"] # returns true
  9. query_people["Wenceslas"] # returns nil (equivalent to false in most tests)

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