diff options
Diffstat (limited to 'activesupport/lib/active_support/core_ext/array/uniq_by.rb')
-rw-r--r-- | activesupport/lib/active_support/core_ext/array/uniq_by.rb | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/activesupport/lib/active_support/core_ext/array/uniq_by.rb b/activesupport/lib/active_support/core_ext/array/uniq_by.rb new file mode 100644 index 0000000000..a09b2302fd --- /dev/null +++ b/activesupport/lib/active_support/core_ext/array/uniq_by.rb @@ -0,0 +1,17 @@ +class Array + # Return an unique array based on the criteria given as a proc. + # + # [1, 2, 3, 4].uniq_by { |i| i.odd? } + # #=> [1, 2] + # + def uniq_by + hash, array = {}, [] + each { |i| hash[yield(i)] ||= (array << i) } + array + end + + # Same as uniq_by, but modifies self. + def uniq_by! + replace(uniq_by{ |i| yield(i) }) + end +end |