Transducer FizzBuzz

fizzducer.rb

require 'transducers'

T = Transducers

fizzducer = T.compose T.map { |n| n % 3 == 0 && n % 5 == 0 && 'FizzBuzz' || n },
                      T.map { |n| n % 3 == 0 && 'Fizz' || n },
                      T.map { |n| n % 5 == 0 && 'Buzz' || n },
                      T.map(:to_s)

T.transduce fizzducer, :puts, STDOUT, 1.upto(5)
#>> 1
#>> 2
#>> Fizz
#>> 4
#>> Buzz

T.transduce fizzducer, :<<, '', [1, 2, 3, 4, 5]
#=> "12Fizz4Buzz"

T.transduce T.compose(fizzducer, T.map { |n| n << "\n" }), :<<, '', 1..5
#=> "1\n2\nFizz\n4\nBuzz\n"

T.transduce T.compose(fizzducer, T.map(:to_i)), :+, 0, 1..5
#=> 7

T.transduce fizzducer, :<<, [], 1.upto(5)
#=> ["1", "2", "Fizz", "4", "Buzz"]