Group and count in Ruby

Ruby

tally does the counting; group_by keeps the members when you need them.

words.tally
#=> {"the"=>12, "and"=>7}

orders.group_by(&:status)
      .transform_values(&:count)

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Ruby ruby enumerable chris

More in Ruby

Safe navigation and fetch in Ruby Ruby &. stops at nil; fetch raises rather than returning nil when a key is genuinely required.

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