Comparing ruby and go

README.md

Comparison of a simple, idiomatic ruby program to a similar go program.

To run the ruby program: ruby mammals.rb

To run the go program: go run mammals.go

Read the detailed comparison on my blog.

mammals.go

package main

import (
	"fmt"
	"strings"
)

type Mammal struct {
	name  string
	group string
}

var mammals = []Mammal{
	Mammal{"Baboon", "Primates"},
	Mammal{"Dingo", "Carnivora"},
	Mammal{"Bison", "Artiodactyla"},
	Mammal{"Gerbil", "Rodentia"},
	Mammal{"Bear", "Carnivora"},
	Mammal{"Chimpanzee", "Primates"},
	Mammal{"Deer", "Artiodactyla"},
	Mammal{"Fox", "Carnivora"},
	Mammal{"Hamster", "Rodentia"},
	Mammal{"Jaguar", "Carnivora"},
}

func main() {
	groupedMammals := make(map[string][]string)

	for _, mammal := range mammals {
		_, ok := groupedMammals[mammal.group]
		if !ok {
			groupedMammals[mammal.group] = make([]string, 0)
		}
		groupedMammals[mammal.group] = append(groupedMammals[mammal.group], mammal.name)
	}

	for group, animalNames := range groupedMammals {
		fmt.Printf("%s: %s\n", group, strings.Join(animalNames, ", "))
	}
}

mammals.rb

class Mammal
  attr_accessor :name, :group

  def initialize(name, group)
    self.name = name
    self.group = group
  end
end

mammals = [
  Mammal.new('Baboon', 'Primates'),
  Mammal.new('Dingo', 'Carnivora'),
  Mammal.new('Bison', 'Artiodactyla'),
  Mammal.new('Gerbil', 'Rodentia'),
  Mammal.new('Bear', 'Carnivora'),
  Mammal.new('Chimpanzee', 'Primates'),
  Mammal.new('Deer', 'Artiodactyla'),
  Mammal.new('Fox', 'Carnivora'),
  Mammal.new('Hamster', 'Rodentia'),
  Mammal.new('Jaguar', 'Carnivora')
]

grouped_mammals = {}
mammals.each do |mammal|
  grouped_mammals[mammal.group] ||= []
  grouped_mammals[mammal.group] << mammal.name
end

grouped_mammals.each do |group, mammal_names|
  puts "#{group}: #{mammal_names.join(', ')}"
end