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deepfryed/uniq_by.rb

Created February 15, 2012 03:17
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unique { f(n) | n ϵ N }
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uniq_by.rb
module Enumerable
def uniq_by &block
seen = {}
reject {|value| seen.key?(block.call(value)) ? true : seen[block.call(value)] = false}
end
end
@deepfryed
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the following does the same but uses more memory depending on dupes

list.group_by(&:method).values.map(&:first)

@deepfryed
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just so you know, you can do the following only for arrays

list.uniq(&:method)

yeah, dan schooled me - you can gloat dan

@tigris
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tigris commented Feb 15, 2012

Where's my credit, noob :P

@deepfryed
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well i need find a good optometrist for dan /O-O/

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