Ruby 2.2 で追加されたメソッドまとめをみてた。 New Methods in Ruby 2.2 Enumerable#slice_whenのユースケースでEnumerable内での各要素出現数をカウントするのがステキだったので、2.2以前も含めてどう書けるパターンあるんだっけ?をメモ。 カウント対象のArrayを生成 labels = ["aaa", "bbb", "ccc"] ary = Array.new(20) { labels.sample } puts ary.join ", " # bbb, aaa, bbb, bbb, bbb, aaa, ccc, aaa, aaa, bbb, ccc, ccc, bbb, bbb, aaa, aaa, ccc, bbb, aaa, aaa
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